Ward Prep: Brs Ch 4 Genetic Disorders

Front 1

what is the most frequently occuring chromosomal disorder

Back 1

Down syndrome

Front 2

4 changes of appearance/behvaior in Down Syndrome

Back 2

1) MR 2) Epicanthal folds (inner upper eyelid) 3) Brushfield spots (white spots in the periphery of the iris) 4) single palmar crease

Front 3

complications of down syndrome (3)

Back 3

1) congenital heart dz (endocardial cushion defects: AV valve malformations, atrial or ventricular septal defects) 2) leukemia (lymphoblastic) 3) inc susceptibility to infection

Front 4

maternal screening for down syndrome: what are the lab abnormalities

Back 4

1) low alpha fetoprotein 2) low unconjugated estriol 3) high human Chorionic Gonadotropin

Front 5

manifestations of Cri du Chat syndrome (4)

Back 5

1) MR 2) Cat like cry 3) microcephaly 4) hypertelorism "oliver"

Front 6

Manifestations of DiGeorge syndrome (5)

Back 6

CATCH 22. Congenital heart disease, Abnormal faces, Thymic hypoplasia => T cell deficit, Cleft palate, Hypoparathyroidism => hypocalcemia, microdeletion on chromosome 22

Front 7

Edwards syndrome is caused by

Back 7

trisomy 18 (Edwards = election age)

Front 8

Manifestations of Edwards syndrome (4)

Back 8

1) MR 2) Micrognathia 3) CHD 4) rocker bottom feet. Same as Patau syndrome except Micrognathia instead of Microcephaly/microphthalmia

Front 9

Patau syndrome is caused by

Back 9

trisomy 13

Front 10

Manifestations of Patau syndrome (5)

Back 10

MR, microcephaly/ophthalmia, CHD, rocker bottom feet. Same as Edwards syndrome except microcephaly/microphtalmia instead of micrognathia

Front 11

name 3 sex chromosome abnormalities and their karyotype

Back 11

1) Klinefelter syndrome XX(+) Y(+): male with hypogonadism (dec T, inc LH FSH, gynecomasty, eunuchoid appearance) 2) XYY (violent behavior, tall, acne) 3) Turner syndrome (XO). Hypogonadism (streak ovaries). Short, webbed neck, coarctation of aorta, auto-antibody hypothyroidism. MCC 1° amenorrhea. "tina turner". 4) XXX is usu w/o clinical abn. maybe menstrual irregularities. >3X => MR

Front 12

Are abnormalities of sex chromosomes a/w mental retardation?

Back 12

No. If present, worse with more X's above 3

Front 13

What's the mcc of primary amenorrhea

Back 13

Turner syndrome (XO)

Front 14

Features of klinefelter syn

Back 14

XXY. Hypogonadism => low T => high FSH LH, gynecomastia, eunuchoid appearance

Front 15

Features of turner syndrome

Back 15

XO. Hypogonadism (streak ovaries) => poorly developed genetalia. Short stature, webbed neck, coarctation of the aort, autoabs hypothyroidism

Front 16

Name 3 trinucleotide repeat disorders

Back 16

Fragile X syndrome, huntington's disease, myotonic dystrophy. Marked by anticipation.

Front 17

manifestations of Fragile X syndrome, inheritance

Back 17

MR (2nd mcc after down syn) + macro-orchidism (males). Few number of repeats = carrier. Males only pass it to females. Expansion only happens in females, who pass it on to females, males. Males with full mutations have MR + macro-orchidism. Only half females with full mutations have MR.

Front 18

Name 2 disorders a/w genomic imprinting and distinguish between their inheritance pattern

Back 18

Same gene, but syn deponds on whether chromosome deletion was transmitted by father or mother (dep on paternal/maternal imprinting). Prader-willi syn = "Paternal Willy". Angelman = "angelmom".

Front 19

Manifestations of Prader-Willi syndrome

Back 19

MR, hypogonadism, uncontrolled appetite => obseity + diabetes. Paternal inheritance.

Front 20

Manifestations of Angelman syndrome

Back 20

MR, happy puippet syndrome (happy demeanor, hand flapping). Maternal inheritance.

Front 21

Familial Hypercholesterolemia. Defect? Manifestations?

Back 21

LDLR defect => reduced uptake of LDL => hyper cholesterolemia => early atherosclerosis, xanthomas

Front 22

Marfan Syndrome. Defect? Manifestations?

Back 22

Fibrillin. Ectopia lentis, arachnodactyly, pectus excavatum, aneurysm/dissecton of the aorta, MVP, AR

Front 23

Neurofibromatosis type I triad

Back 23

1) distributed neurofibromas (bilateral vestibular schwannomas implies type II) 2) café au lait spots 4) lisch nodules (pigmented hamartomas of the iris)

Front 24

Phenylketonuria. Defect? Px? Tx? When stop tx?

Back 24

Mutation in phenylalanine hydroxylase which converts phenylalanine to tyrosine in the liver. Build up of phenylalanine and phenylalanine breakdown products. Px: mental deterioration (by 1 yo), blond/blue eyed, musty body odor. Tx: phe free diet. Can eat during adult hood. But stop again during pregnancy or else MR/GR, CHD.

Front 25

Alkaptonuria. What builds up? Px?

Back 25

Build up of homogenistic acid => urine => turns dark on standing. Ochronosis (dark pigmentation of connective tissue) => ochronotic arthritis.

Front 26

Maple syrup urine disease. Defect? Explain the name.

Back 26

Defect in break down of branched amino acid => keto acids of branched amino acids in urine (leucine, isoleucine, valine) => smells like urine. Neonatal death.

Front 27

Cystic Fibrosis. Pathophys

Back 27

Chloride channel transport defect (most often ∆F508) => viscid mucus secretions + salty sweat. Viscid mucus => 1) Lungs: chronic pulmonary dz. Bronchiectasis, bronchitis, pulmonary infections (Pseudomonas, aureus, burkholderia). 2) Pancreas: biliary obstruction => chronic pancreatitis => pancreatic insufficiency 3) Intestines: can px w/ meconium ileus

Front 28

name 2 disorders that are balanced polymorphisms for malaria

Back 28

Hemoblobin S (heterozygotes are relatively resistant to plasmodium falciparum; homo = sickle cell anemia). Glucose-6-Phosphate Dehydrogenase deficiency (G6PD prod NADPH which acts as an antioxidant; oxidative stress => hemolytic anemia)

Front 29

distinguish between true hermaphroditism and pseudohermaphroditism

Back 29

true: genetic male (has Y), gonads tissues of both, genitals ambig. Pseudo: genetic/gonads male or female, genitals amiguous.

Front 30

causes of male pseudohermaphroditism

Back 30

tissue resistance to androgens (testicular feminization by defect in T R), dec T synth, hormones during pregnancy. Genetic/Gonad: male. Genitals: ambig

Front 31

causes of female pseudohermaphroditism

Back 31

Congenital adrenal hyperplasia, androgen secreting tumor (adrenal, ovarian), hormones during pregnancy. Genetic/gonads female. Genitals: ambig