Prader-Willi Syndrome and Angelman Syndrome

Overview

Definitions

Prader-Willi syndrome ( PWS PWS A vascular malformation of developmental origin characterized pathologically by ectasia of superficial dermal capillaries, and clinically by persistent macular erythema. In the past, port wine stains have frequently been termed capillary hemangiomas, which they are not; unfortunately this confusing practice persists: hemangioma, capillary is neoplastic, a port-wine stain is non-neoplastic. Port-wine stains vary in color from fairly pale pink to deep red or purple and in size from a few millimeters to many centimeters in diameter. The face is the most frequently affected site and they are most often unilateral. Sturge-Weber Syndrome (SWS)) is a condition associated with loss of the paternal chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 15q11-13 region and is characterized by intellectual disability Disability Determination of the degree of a physical, mental, or emotional handicap. The diagnosis is applied to legal qualification for benefits and income under disability insurance and to eligibility for social security and workman’s compensation benefits. ABCDE Assessment, short stature, underdevelopment of the sexual organs, and obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity.

Angelman syndrome (AS) is a disorder associated with loss of the maternal chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 15q11-13 region and is characterized by severe neurodevelopmental delay.

Epidemiology

• PWS PWS A vascular malformation of developmental origin characterized pathologically by ectasia of superficial dermal capillaries, and clinically by persistent macular erythema. In the past, port wine stains have frequently been termed capillary hemangiomas, which they are not; unfortunately this confusing practice persists: hemangioma, capillary is neoplastic, a port-wine stain is non-neoplastic. Port-wine stains vary in color from fairly pale pink to deep red or purple and in size from a few millimeters to many centimeters in diameter. The face is the most frequently affected site and they are most often unilateral. Sturge-Weber Syndrome (SWS):
  • Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency is about 1 in 15,000 to 1 in 30,000 live births in the United States, and affects between 350,000 and 400,000 individuals worldwide.
  • Both sexes are affected equally.
• AS:
  • Prevalence Prevalence The total number of cases of a given disease in a specified population at a designated time. It is differentiated from incidence, which refers to the number of new cases in the population at a given time. Measures of Disease Frequency of AS is about 1 in 10,000 to 1 in 20,000 live births.
  • No gender Gender Gender Dysphoria or racial predominance 
• Vast majority of cases are sporadic Sporadic Selective IgA Deficiency rather than familial.

Etiology

• Prader-Willi syndrome: loss of paternal copy of the chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 15q11-13 region
• Angelman syndrome: loss of maternal copy of the chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 15q11-13 region

Pathophysiology

Both PWS PWS A vascular malformation of developmental origin characterized pathologically by ectasia of superficial dermal capillaries, and clinically by persistent macular erythema. In the past, port wine stains have frequently been termed capillary hemangiomas, which they are not; unfortunately this confusing practice persists: hemangioma, capillary is neoplastic, a port-wine stain is non-neoplastic. Port-wine stains vary in color from fairly pale pink to deep red or purple and in size from a few millimeters to many centimeters in diameter. The face is the most frequently affected site and they are most often unilateral. Sturge-Weber Syndrome (SWS) and AS are associated with genomic imprinting Imprinting The variable phenotypic expression of a gene depending on whether it is of paternal or maternal origin, which is a function of the DNA methylation pattern. Imprinted regions are observed to be more methylated and less transcriptionally active. Epigenetic Regulation, which is the differential expression of certain genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure based on inheritance from a specific parent.

Angelman syndrome

• AS is caused by the absence of a maternal copy of the UBE3A gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics:
  • The UBE3A gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics encodes E6-associated protein ubiquitin protein ligase 3A.
  • Only the maternally inherited copy of UBE3A is functional in certain areas of the brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification; the paternal copy is silent.
• Most cases (> 70%) are caused by the absence of maternal homologous segment (microdeletion). 
• A smaller percentage of cases is caused by uniparental disomy (duplication of paternal 15q segment), translocations, or mutations.

Prader-Willi syndrome

• PWS PWS A vascular malformation of developmental origin characterized pathologically by ectasia of superficial dermal capillaries, and clinically by persistent macular erythema. In the past, port wine stains have frequently been termed capillary hemangiomas, which they are not; unfortunately this confusing practice persists: hemangioma, capillary is neoplastic, a port-wine stain is non-neoplastic. Port-wine stains vary in color from fairly pale pink to deep red or purple and in size from a few millimeters to many centimeters in diameter. The face is the most frequently affected site and they are most often unilateral. Sturge-Weber Syndrome (SWS) is caused by:
  • Absence of paternal homologous segment (microdeletion) in 70% of cases 
  • Duplication of maternal chromosome Chromosome In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. Basic Terms of Genetics 15q segment (uniparental disomy) in 25% of cases
  • The rest (5%) are caused by translocations or mutations.
• The end result is an absence of working copies of about 7 genes Genes A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. DNA Types and Structure, as parts of maternal chromosomes Chromosomes In a prokaryotic cell or in the nucleus of a eukaryotic cell, a structure consisting of or containing DNA which carries the genetic information essential to the cell. DNA Types and Structure are inactive by default; require paternal counterpart to function.

Clinical Presentation

Prader-Willi syndrome

• At birth:
  • Hypotonia Hypotonia Duchenne Muscular Dystrophy and lethargy Lethargy A general state of sluggishness, listless, or uninterested, with being tired, and having difficulty concentrating and doing simple tasks. It may be related to depression or drug addiction. Hyponatremia
  • Feeding and breathing difficulty
  • Undescended testes Testes Gonadal Hormones in males
• Childhood:
  • Hyperphagia, insatiable appetite, weight gain, and obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity due to high ghrelin Ghrelin A 28-amino acid, Acylated, orexigenic peptide that is a ligand for growth hormone secretagogue receptors. Ghrelin is widely expressed but primarily in the stomach in the adults. Ghrelin acts centrally to stimulate growth hormone secretion and food intake, and peripherally to regulate energy homeostasis. Its large precursor protein, known as appetite-regulating hormone or motilin-related peptide, contains ghrelin and obestatin. Glucagonoma levels
  • Small hands and feet
  • Strabismus Strabismus Strabismus is the misalignment of the eyes while fixating the gaze on an object. Strabismus can be idiopathic, but it may also be caused by cerebral palsy, uncorrected refractive errors, and extraocular muscle or cranial nerve dysfunction. Strabismus
  • Speech delay
  • Mild intellectual disabilities and behavioral issues
• Adulthood:
  • Borderline intellectual capability
  • Short stature
  • Hypogonadism Hypogonadism Hypogonadism is a condition characterized by reduced or no sex hormone production by the testes or ovaries. Hypogonadism can result from primary (hypergonadotropic) or secondary (hypogonadotropic) failure. Symptoms include infertility, increased risk of osteoporosis, erectile dysfunction, decreased libido, and regression (or absence) of secondary sexual characteristics. Hypogonadism 
  • Facial features:
    • Almond-shaped eyes
    • Narrow forehead Forehead The part of the face above the eyes. Melasma
    • Triangular mouth

Angelman syndrome

• At birth:
  • Microcephaly Microcephaly A congenital abnormality in which the cerebrum is underdeveloped, the fontanels close prematurely, and, as a result, the head is small. (desk reference for neuroscience, 2nd ed. ). Fetal Alcohol Spectrum Disorder
  • Feeding issues
• Childhood and adulthood:
  • Severe developmental delay
  • Behavioral: inappropriate laughter, seemingly happy demeanor, short attention Attention Focusing on certain aspects of current experience to the exclusion of others. It is the act of heeding or taking notice or concentrating. Psychiatric Assessment span (“happy puppet syndrome”)
  • Lack of proper speech, use of nonverbal communication Communication The exchange or transmission of ideas, attitudes, or beliefs between individuals or groups. Decision-making Capacity and Legal Competence skills
  • Movement disorders such as ataxia Ataxia Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or peripheral nerve diseases. Motor ataxia may be associated with cerebellar diseases; cerebral cortex diseases; thalamic diseases; basal ganglia diseases; injury to the red nucleus; and other conditions. Ataxia-telangiectasia, fine tremors, jerky movements
  • Prominent mandible Mandible The largest and strongest bone of the face constituting the lower jaw. It supports the lower teeth. Jaw and Temporomandibular Joint: Anatomy, flat head
  • Strabismus Strabismus Strabismus is the misalignment of the eyes while fixating the gaze on an object. Strabismus can be idiopathic, but it may also be caused by cerebral palsy, uncorrected refractive errors, and extraocular muscle or cranial nerve dysfunction. Strabismus
  • Seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures (onset by 3 years) and abnormal EEG EEG Seizures tracings
  • Sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disturbances

Diagnosis

Prader-Willi syndrome

• Genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies:
  • DNA DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA Types and Structure methylation Methylation Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. . Glucocorticoids testing: detects parent-specific imprinting Imprinting The variable phenotypic expression of a gene depending on whether it is of paternal or maternal origin, which is a function of the DNA methylation pattern. Imprinted regions are observed to be more methylated and less transcriptionally active. Epigenetic Regulation of the specific chromosome 15 Chromosome 15 Marfan Syndrome region
  • Establishes diagnosis in > 99% of patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship
• Clinical criteria for genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies:
  • Birth to 2 years:
    • Hypotonia Hypotonia Duchenne Muscular Dystrophy with poor suck and poor weight gain
    • Cryptorchidism Cryptorchidism Cryptorchidism is one of the most common congenital anomalies in young boys. Typically, this asymptomatic condition presents during a routine well-child examination where 1 or both testicles are not palpable in the scrotum. Cryptorchidism in boys
  • 2–6 years:
    • Hypotonia Hypotonia Duchenne Muscular Dystrophy with history of poor suck
    • Global developmental delay
    • Short stature and/or growth failure Growth failure Chronic Granulomatous Disease associated with accelerated weight gain
  • 6–12 years:
    • History of hypotonia Hypotonia Duchenne Muscular Dystrophy with poor suck ( hypotonia Hypotonia Duchenne Muscular Dystrophy often persists)
    • Global developmental delay
    • Excessive eating (hyperphagia (obsession with food)), with obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity if food intake is uncontrolled
  • 13 years through adulthood:
    • Cognitive impairment (usually mild intellectual disability Disability Determination of the degree of a physical, mental, or emotional handicap. The diagnosis is applied to legal qualification for benefits and income under disability insurance and to eligibility for social security and workman’s compensation benefits. ABCDE Assessment)
    • Excessive eating (hyperphagia), with central obesity Central Obesity Cushing Syndrome if uncontrolled
    • Hypogonadism Hypogonadism Hypogonadism is a condition characterized by reduced or no sex hormone production by the testes or ovaries. Hypogonadism can result from primary (hypergonadotropic) or secondary (hypogonadotropic) failure. Symptoms include infertility, increased risk of osteoporosis, erectile dysfunction, decreased libido, and regression (or absence) of secondary sexual characteristics. Hypogonadism (e.g., delayed puberty Delayed Puberty Delayed puberty (DP) is defined as the lack of testicular growth in boys past the age of 14 and the lack of thelarche in girls past the age of 13. Delayed puberty affects up to 5% of healthy boys and girls, and half of all cases are due to constitutional growth delay. Delayed Puberty)
    • Typical behavior problems (including temper tantrums and obsessive-compulsive features)

Angelman syndrome

• Genetic testing Genetic Testing Detection of a mutation; genotype; karyotype; or specific alleles associated with genetic traits, heritable diseases, or predisposition to a disease, or that may lead to the disease in descendants. It includes prenatal genetic testing. Myotonic Dystrophies:
  • DNA DNA A deoxyribonucleotide polymer that is the primary genetic material of all cells. Eukaryotic and prokaryotic organisms normally contain DNA in a double-stranded state, yet several important biological processes transiently involve single-stranded regions. DNA, which consists of a polysugar-phosphate backbone possessing projections of purines (adenine and guanine) and pyrimidines (thymine and cytosine), forms a double helix that is held together by hydrogen bonds between these purines and pyrimidines (adenine to thymine and guanine to cytosine). DNA Types and Structure methylation Methylation Addition of methyl groups. In histo-chemistry methylation is used to esterify carboxyl groups and remove sulfate groups by treating tissue sections with hot methanol in the presence of hydrochloric acid. . Glucocorticoids study is the 1st test.
  • This test is followed by genomic hybridization Hybridization The genetic process of crossbreeding between genetically dissimilar parents to produce a hybrid. Blotting Techniques technique to detect specific deletion (class 1 (more severe) or class 2).
  • If negative, perform uniparental disomy studies
• Clinical diagnostic criteria:
  • History of neurodevelopmental, cognitive, and speech development delay
  • History of seizures Seizures A seizure is abnormal electrical activity of the neurons in the cerebral cortex that can manifest in numerous ways depending on the region of the brain affected. Seizures consist of a sudden imbalance that occurs between the excitatory and inhibitory signals in cortical neurons, creating a net excitation. The 2 major classes of seizures are focal and generalized. Seizures
  • General happy demeanor, inappropriate laughter
  • Characteristic facies
  • Odd limb movements, such as hand Hand The hand constitutes the distal part of the upper limb and provides the fine, precise movements needed in activities of daily living. It consists of 5 metacarpal bones and 14 phalanges, as well as numerous muscles innervated by the median and ulnar nerves. Hand: Anatomy flapping
  • Fine tremors, jerky joint dispositions, seemingly spastic wide-based gait Wide-based gait Normal Pressure Hydrocephalus

Management

Prader-Willi syndrome management

• Diet modification for obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity
• Behavioral therapy, possible selective serotonin reuptake inhibitors Selective Serotonin Reuptake Inhibitors Serotonin Reuptake Inhibitors and Similar Antidepressants ( SSRIs SSRIs Serotonin Reuptake Inhibitors and Similar Antidepressants) for obsessive-compulsive behaviors
• Speech therapy Speech Therapy Treatment for individuals with speech defects and disorders that involves counseling and use of various exercises and AIDS to help the development of new speech habits. Myotonic Dystrophies
• Physical therapy Physical Therapy Becker Muscular Dystrophy
• Human growth hormone Human growth hormone A 191-amino acid polypeptide hormone secreted by the human adenohypophysis, also known as gh or somatotropin. Synthetic growth hormone, termed somatropin, has replaced the natural form in therapeutic usage such as treatment of dwarfism in children with growth hormone deficiency. Idiopathic Intracranial Hypertension may improve stamina and muscle mass Mass Three-dimensional lesion that occupies a space within the breast Imaging of the Breast, but is associated with tonsillar hypertrophy Hypertrophy General increase in bulk of a part or organ due to cell enlargement and accumulation of fluids and secretions, not due to tumor formation, nor to an increase in the number of cells (hyperplasia). Cellular Adaptation, which can cause early demise.
• Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas:
  • Usually reach adulthood
  • Able to function in a group setting and do vocational work
  • Some patients Patients Individuals participating in the health care system for the purpose of receiving therapeutic, diagnostic, or preventive procedures. Clinician–Patient Relationship can attend community colleges.

Angelman syndrome management

• EEG EEG Seizures, analysis, and treatment of seizure disorder with anticonvulsant Anticonvulsant Anticonvulsant drugs are pharmacological agents used to achieve seizure control and/or prevent seizure episodes. Anticonvulsants encompass various drugs with different mechanisms of action including ion-channel (Na+ and Ca+2) blocking and GABA reuptake inhibition. First-Generation Anticonvulsant Drugs drugs
• Address feeding problems.
• Physical therapy Physical Therapy Becker Muscular Dystrophy to help with ataxia Ataxia Impairment of the ability to perform smoothly coordinated voluntary movements. This condition may affect the limbs, trunk, eyes, pharynx, larynx, and other structures. Ataxia may result from impaired sensory or motor function. Sensory ataxia may result from posterior column injury or peripheral nerve diseases. Motor ataxia may be associated with cerebellar diseases; cerebral cortex diseases; thalamic diseases; basal ganglia diseases; injury to the red nucleus; and other conditions. Ataxia-telangiectasia
• Speech and occupational therapy Occupational Therapy Skilled treatment that helps individuals achieve independence in all facets of their lives. It assists in the development of skills needed for independent living. Fetal Alcohol Spectrum Disorder
• Clonidine Clonidine An imidazoline sympatholytic agent that stimulates alpha-2 adrenergic receptors and central imidazoline receptors. It is commonly used in the management of hypertension. Sympathomimetic Drugs and melatonin to help with sleep Sleep A readily reversible suspension of sensorimotor interaction with the environment, usually associated with recumbency and immobility. Physiology of Sleep disturbances
• Prognosis Prognosis A prediction of the probable outcome of a disease based on a individual’s condition and the usual course of the disease as seen in similar situations. Non-Hodgkin Lymphomas:
  • Can have a normal life span with appropriate interventions
  • Severe intellectual disability Disability Determination of the degree of a physical, mental, or emotional handicap. The diagnosis is applied to legal qualification for benefits and income under disability insurance and to eligibility for social security and workman’s compensation benefits. ABCDE Assessment

Differential Diagnosis

• Fragile X syndrome Fragile X syndrome Fragile X syndrome (FXS), also known as Martin-Bell syndrome, is a genetic condition with X-linked inheritance. Both boys and girls may be affected, but the severity is much worse in boys. Characteristic features include a long face, prominent forehead and chin, large ears, flat feet, and large testes post-puberty for boys. Fragile X Syndrome: a genetic abnormality on the X chromosome X chromosome The female sex chromosome, being the differential sex chromosome carried by half the male gametes and all female gametes in human and other male-heterogametic species. Basic Terms of Genetics that leads to intellectual disability Disability Determination of the degree of a physical, mental, or emotional handicap. The diagnosis is applied to legal qualification for benefits and income under disability insurance and to eligibility for social security and workman’s compensation benefits. ABCDE Assessment and behavioral disorders. Diagnosis is with molecular DNA analysis DNA analysis Biochemical identification of mutational changes in a nucleotide sequence. Hyper-IgM Syndrome. Treatment is supportive.
• Craniopharyngioma Craniopharyngioma Craniopharyngiomas are rare squamous epithelial tumors with a solid and/or cystic structure that arise from the remnants of Rathke’s pouch along the pituitary stalk, in the suprasellar region. Craniopharyngiomas are histologically benign but tend to invade surrounding structures; thus, they should be treated as low-grade malignancies. Craniopharyngioma: a slow-growing, noncancerous Noncancerous Benign Bone Tumors brain Brain The part of central nervous system that is contained within the skull (cranium). Arising from the neural tube, the embryonic brain is comprised of three major parts including prosencephalon (the forebrain); mesencephalon (the midbrain); and rhombencephalon (the hindbrain). The developed brain consists of cerebrum; cerebellum; and other structures in the brain stem. Nervous System: Anatomy, Structure, and Classification tumor Tumor Inflammation that develops near the pituitary Pituitary A small, unpaired gland situated in the sella turcica. It is connected to the hypothalamus by a short stalk which is called the infundibulum. Hormones: Overview and Types gland and the hypothalamus Hypothalamus The hypothalamus is a collection of various nuclei within the diencephalon in the center of the brain. The hypothalamus plays a vital role in endocrine regulation as the primary regulator of the pituitary gland, and it is the major point of integration between the central nervous and endocrine systems. Hypothalamus. The tumor Tumor Inflammation most commonly affects children between 5 and 10 years of age; however, adults can sometimes be affected.
• Cohen syndrome: a congenital Congenital Chorioretinitis condition manifesting with obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity, hypotonia Hypotonia Duchenne Muscular Dystrophy, intellectual disabilities, distinctive facial features with prominent upper central teeth Teeth Normally, an adult has 32 teeth: 16 maxillary and 16 mandibular. These teeth are divided into 4 quadrants with 8 teeth each. Each quadrant consists of 2 incisors (dentes incisivi), 1 canine (dens caninus), 2 premolars (dentes premolares), and 3 molars (dentes molares). Teeth are composed of enamel, dentin, and dental cement. Teeth: Anatomy, and abnormalities of the hands and feet.
• Albright hereditary osteodystrophy Osteodystrophy Cirrhosis: a rare disorder with a wide range of signs and symptoms, including short stature, obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity, round face, subcutaneous ossifications, and brachydactyly. When the disorder is inherited from the mother, resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing to parathyroid Parathyroid The parathyroid glands are 2 pairs of small endocrine glands found in close proximity to the thyroid gland. The superior parathyroid glands are lodged within the parenchyma of the upper poles of the right and left thyroid lobes; the inferior parathyroid glands are close to the inferior tips or poles of the lobes. Parathyroid Glands: Anatomy hormone is found. When inherited from the father, this resistance Resistance Physiologically, the opposition to flow of air caused by the forces of friction. As a part of pulmonary function testing, it is the ratio of driving pressure to the rate of air flow. Ventilation: Mechanics of Breathing is not seen. 
• Spinal muscular atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation: is a neuromuscular disorder with a genetic etiology that causes degenerative changes Degenerative Changes Spinal Stenosis in the spinal cord Spinal cord The spinal cord is the major conduction pathway connecting the brain to the body; it is part of the CNS. In cross section, the spinal cord is divided into an H-shaped area of gray matter (consisting of synapsing neuronal cell bodies) and a surrounding area of white matter (consisting of ascending and descending tracts of myelinated axons). Spinal Cord: Anatomy and brainstem, resulting in progressive muscle weakness and loss of movement due to muscle atrophy Atrophy Decrease in the size of a cell, tissue, organ, or multiple organs, associated with a variety of pathological conditions such as abnormal cellular changes, ischemia, malnutrition, or hormonal changes. Cellular Adaptation. The age of onset, severity of symptoms, and clinical presentation vary by type. It can affect the arm Arm The arm, or “upper arm” in common usage, is the region of the upper limb that extends from the shoulder to the elbow joint and connects inferiorly to the forearm through the cubital fossa. It is divided into 2 fascial compartments (anterior and posterior). Arm: Anatomy and leg Leg The lower leg, or just “leg” in anatomical terms, is the part of the lower limb between the knee and the ankle joint. The bony structure is composed of the tibia and fibula bones, and the muscles of the leg are grouped into the anterior, lateral, and posterior compartments by extensions of fascia. Leg: Anatomy muscles resulting in difficulty walking, as well as difficulty with breathing and swallowing Swallowing The act of taking solids and liquids into the gastrointestinal tract through the mouth and throat. Gastrointestinal Motility.
• Alström syndrome: a rare genetic disorder that affects many body systems including vision Vision Ophthalmic Exam and hearing abnormalities, childhood obesity Obesity Obesity is a condition associated with excess body weight, specifically with the deposition of excessive adipose tissue. Obesity is considered a global epidemic. Major influences come from the western diet and sedentary lifestyles, but the exact mechanisms likely include a mixture of genetic and environmental factors. Obesity, and cardiomyopathy Cardiomyopathy Cardiomyopathy refers to a group of myocardial diseases associated with structural changes of the heart muscles (myocardium) and impaired systolic and/or diastolic function in the absence of other heart disorders (coronary artery disease, hypertension, valvular disease, and congenital heart disease). Cardiomyopathy: Overview and Types. Alström syndrome is caused by mutations in the ALMS1 gene Gene A category of nucleic acid sequences that function as units of heredity and which code for the basic instructions for the development, reproduction, and maintenance of organisms. Basic Terms of Genetics and is of autosomal recessive inheritance Autosomal recessive inheritance Autosomal Recessive and Autosomal Dominant Inheritance.