high yield genetic conditions usmle

gene/pattern marfan syndrome

autosomal dominant

fibrillin 1

gene/pattern ehlers danlos

autosomal dominant

COL5A1/2

gene/pattern neurofibromastosis 1

autosomal dominant

nf1 (chromosome 17)

gene/pattern neurofibromastosis 2

autosomal dominant

nf2 (chromosome 22)

gene/pattern tuberous sclerosis

autosomal dominant

tsc 1/2

gene/pattern von hippel lindau

autosomal dominant

vhl (chromosome 3)

gene/pattern achondroplasia

autosomal dominant

fgfr3

gene/pattern huntington

autosomal dominant/ Trinucleotide Repeat Disorders

cag repeat (chromosome 4)

gene/pattern familial hypercholesteremia

autosomal dominant

ldl receptor

key findings marfan syndrome

Tall, long limbs, lens up, aortic aneurysm

key findings ehlers danlos

Hyperextensible skin, easy bruising

key findings neurofibromastosis 1

Café-au-lait, neurofibromas, Lisch nodules

key findings neurofibromastosis 2

Bilateral vestibular schwannomas

key findings tuberous sclerosis

Seizures, angiofibromas, renal AML

key findings von hippel lindau

Hemangioblastomas, RCC, pheochromocytoma

key findings achondroplasia

Short limbs, normal trunk

key findings familial hypercholesteremia

Xanthomas, early atherosclerosis

key findings huntington

Chorea, dementia, caudate atrophy

gene/ pattern cystic fibrosis

autosomal recessive

CFTR (∆F508)

gene/ pattern sickle cell

autosomal recessive

β-globin (Glu→Val)

gene/ pattern pku

autosomal recessive

Phenylalanine hydroxylase

gene/ pattern tay sachs

autosomal recessive

Hexosaminidase A

gene/ pattern niemann picks

autosomal recessive

Sphingomyelinase

gene/ pattern gaucher

autosomal recessive

Glucocerebrosidase

gene/ pattern wilson disease

autosomal recessive

ATP7B

gene/ pattern Friedreich ataxia

autosomal recessive/ Trinucleotide Repeat Disorders

GAA repeat

presentation CF

Thick mucus, infertility

presentation sickle cell

Hemolysis, vaso-occlusion

presentation pku

Musty odor, intellectual disability

presentation tay sachs

Cherry-red macula, no HSM

presentation niemann pick

Cherry-red + HSM

presentation gaucher

Bone pain, hepatosplenomegaly

presentation wilson disease

Kayser–Fleischer rings, liver/neuro

presentation Friedreich ataxia

ataxia, cardiomyopathy, dm

gene/ pattern Ornithine transcarbamylase deficiency

x linked recessive

gene/ pattern G6PD deficiency

x linked recessive

gene/ pattern fabry disease

x linked recessive

α-galactosidase A

gene/ pattern Wiskott–Aldrich

x linked recessive

was gene

gene/ pattern duchenne md

x linked recessive

Dystrophin (frameshift)

gene/ pattern becker md

x linked recessive

Dystrophin (in-frame)

gene/ pattern Hemophilia A/B

x linked recessive

factor VIII/ IX

gene/ pattern Lesch–Nyhan

x linked recessive

SGPRT

presentation Ornithine transcarbamylase deficiency

raised ammonia

no megaloblastic anemia

presentation fabry disease

Angiokeratomas, renal failure

presentation wiskott aldrich

Eczema, thrombocytopenia, infections

presentation G6PD deficiency

Hemolysis after stress, fava beans

presentation duchenne md

Early death, calf pseudohypertrophy

presentation becker md

Early death, calf pseudohypertrophy

milder/ later onset than duchenne

presentation hemophilia a/b

Hemarthrosis, ↑PTT

presentation lesch-nyan

Self-mutilation, gout

gene/ pattern Leber hereditary optic neuropathy

mitochondrial

gene/pattern MELAS

mitochondrial

gene/ pattern MERRF

mitochondrial

presentation Leber hereditary optic neuropathy

sudden blindness

presentation MELAS

Stroke-like episodes, lactic acidosis

presentation MERRF

Myoclonic epilepsy, ragged-red fibers

gene/ pattern Myotonic dystrophy

trinucleotide repeat disorder

CTG

gene/ pattern fragile x

trinucleotide repeat disorder

cgg

presentation myotonic dystrophy

Myotonia, cataracts

presentation fragile x

Large jaw, ears, macroorchidism

gene/ pattern digeorge

Chromosomal Deletions

22q11

gene/ pattern williams

Chromosomal Deletions

7q

gene/ pattern cri du chat

Chromosomal Deletions

5p

gene/ pattern pradder willi

Chromosomal Deletions

(15q paternal del.)

gene/ pattern angelman

Chromosomal Deletions

(15q maternal del.)

presentation digeorge

Cleft palate, cardiac defects, hypocalcemia

presentation angelman

Seizures, ataxia, happy disposition

presentation cri du chat

Cat cry, microcephaly, VSD

presentation williams

Friendly, hypercalcemia, elfin face

presentation prader willi

Obesity, hypotonia, hypogonadism

associations fetal alcohol syndrome

VSD, PDA, ASD, tetralogy of Fallot

congenital rubella associations

PDA, pulmonary artery stenosis, septal defects

down syndrome associations

AVSD, VSD, ASD

pregnancy w/ diabetes associations

TGA, truncus arteriosus, tricuspid atresia, VSD

marfan associations

MVP, thoracic aortic aneurysm/dissection, AR

lithium associations

Ebstein anomaly

turner syndrome associations

Bicuspid aortic valve, aortic coarctation/dissection

williams syndrome associations

Supravalvular aortic stenosis

22q11 associations

Truncus arteriosus, tetralogy of Fallot