Genetics Flashcards
An autosomal recessive disorder caused by mutations in the CFTR gene (chloride channel) on chromosome 7 and characterized by widespread exocrine gland dysfunction
Cystic fibrosis
Almost all cases of meconium ileum is due to
Cystic fibrosis
recurrent pulmonary infections (especially with Pseudomonas and S aureus) with subsequent cyanosis, digital clubbing, chronic cough (the most common pulmonary symptom), dyspnea, bronchiectasis, hemoptysis, chronic sinusitis, rhonchi, rales, hyperresonance to percussion, and nasal polyposis.
Cystic fibrosis
Go symptoms in infancy and plump symptoms in adult
The most common chromosomal fiercer and cause of mental retardation
Associated with advanced maternal age
Down Syndrome
Ups panted epicanthic folds flat facial profile
Simian crease, general hypotonia,
Associated with duodenal atresia, hirschsprung disease, CHD (most commonly AV canal malformation)
Inc risk for ALL, hypothyroidism and Alzheimer’s
Down syndrome
Rocker bottom feet, micrognathia, low set ears, clenched hands, prominent occiput,
CHD
Horseshoe kidneys
Edwards’ syndrome
Trisomy 18
Microphthalmia Holoprosencephaly Microcephaly Cleft lip and palate Polydactyly Punched out scalp lesions Omphalocoele CHD
Patau syndrome Trisomy 13
47 XXY Advanced maternal age Most common causes of hypogonadism Testicular atrophy Tall Long extremities Gynecomastia Female hair distribution
Klinefelter’s syndrome
Not associated with maternal age Primary amenorrhea Ovarian dysgenesis Short stature Widely spaced nipples Shield chest Webbed neck Coarctation of aorta May have lymphedema of hands and feet of neonatal period May have horseshoe kidney
Turner’s syndrome 45 XO
Very tall with severe acne and antisocial behavior
47 XYY
Double Y Males
Decreased phenylalanine hydroxylase Fair hair and skin Eczema Blond hair Blue eyes Musty urine odor Presents after a few months of life
Phenylketonuria
Second most common cause of mental retardation
Large jaw, testes, ears
Autistic behaviors
Fragile X syndrome
X-linked recessive Severe. Neuropathic limb pain Joint swelling Angiokeratomas Telangiectasia Lack of alpha-galactosidase A that leads to accumulation of ceramide trihexoside in the heart brain and kidneys
Fabry’s disease
Absence of hexosaminidase
Weakness and slow growth
Dead by 3 years of age
Cherry red spot without hepatosplenomegaly
Tay Sachs Disease
