autosomal dominant Flashcards
achondroplasia
cell signaling defect of fibroblast growth factor (FGF) receptor 3 - inhibit chondrocytes, cartilage growth (epiphyseal plate).
results in dwarfism.
short limbs, normal head and trunk.
increased age of which parent assoc. with achondroplasia?
father
ADPKD
always BILATERAL.
massive kidneys due to multiple large cysts.
presentation of ADPKD
flank pain.
hematuria.
HTN.
progressive renal failure.
90% ADPKD due to mutation in…
PKD1 on chromo 16
16 letters in “polycystic kidney”
what other organ systems is ADPKD assoc. with?
polycystic liver disease.
berry aneurysms.
mitral valve prolapse.
familial adenomatous polyposis
colon is COVERED with adenomatous polyps after puberty.
progresses to COLON CANCER unless resected.
FAP gene mutation
APC gene on chromo 5
5 letters in “polyp”
familial hypercholesterolemia
hyperlipidemia type IIA.
elevated LDL due to defective or absent LDL receptor.
features of familial hypercholesterolemia (HOMOZYGOTE)
severe atherosclerotic dz early in life.
tendon xanthomas (Achilles).
MI may develop before age 20.
chol levels in familial hypercholesterolemia
heterozygote 300 mg/dL (1:500).
homozygote 700+ mg/dL (VERY RARE).
hereditary hemorrhagic telangiectasias
Osler-Weber-Rendu syndrome
inherited d/o of bld vessels.
telangiectasias. recurrent epistaxis. GI bleed, hematuria. skin discolorations. AVMs.
hereditary spherocytosis
spheroid RBCs due to SPECTRIN or ANKYRIN defect.
hemolytic anemia.
increased MCHC**
cure for hereditary spherocytosis
splenectomy
Huntington’s disease
trinucleotide repeat d/o (CAG).
gene on chromo 4 (“Hunting 4 food”).
findings in Huntington’s disease
depression. progressive dementia. choreiform mvmts. CAUDATE atrophy. decreased levels of GABA and ACh in brain.
sx manifest between age 20-50.
Marfan’s syndrome
fibrillin gene mutation (ECM glycoprot).
conn tissue d/o affecting skeleton, heart, eyes.
findings in Marfan’s syndrome
tall w/ long extremities. pectus excavatum. hyperextensive joints. long tapering fingers/toes (arachnodactyly). subluxation of lenses**
how does Marfan’s syndrome affect heart?
cystic medial necrosis of aorta =
aortic incompetence, dissecting aortic aneurysms.
floppy mitral valve.
multiple endocrine neoplasias (MEN)
1, 2A, 2B.
familial tumors of endocrine glands.
what gene are MEN 2A and 2B assoc with?
ret
neurofibromatosis type 1 (von Recklinghausen’s disease)
affects neurofibromin.
long arm of chromo 17 (17 letters in “von Recklinghausen”).
features of NF1
cafe au lait spots. neural tumors. Lisch nodules (iris). skel d/o, scoliosis. optic pathway gliomas.
Lisch nodules
pigmented iris hamartomas
neurofibromatosis type 2
affects merlin.
NF2 gene on chromo 22.
features of NF2
bilateral acoustic scwannomas.
juvenile cataracts.
tuberous sclerosis
facial lesions (adenoma sebaceum). ash leaf spots on skin. cortical and retinal hamartomas. seizures. MR. renal cysts. renal angiomyolipoma. cardiac rhabdomyoma. increased incidence of astrocytoma.
genetic features of tuberous sclerosis
incomplete penetrance.
variable presentation.
von Hippel-Lindau disease
deletion of VHL gene (tumor suppressor) on chromo 3p.
results in constitutive expression of HIF (transcription factor) and activation of angiogenic growth factors.
features of von Hippel-Lindau disease
hemagioblastomas (retinal, cerebellum, medulla).
50% develop bilateral RCC and other tumors.
Li Fraumeni syndrome
inherited p53 mutation
