Genetic Disorders Flashcards
Osteogenesis imperfecta
Defect in type 1 collagen
Brittle bones, blue sclera, other problems
8 types: type 1 (tarda) mildest, type 2 most severe (congenita), type 4 most common (deforming with normal sclera)
Ehlers-Danlos Syndromes (EDS)
Mutation to pro-alpha collagen gene or modification enzyme: prolyl hydroxylase, lysyl hydroxylase, lysyl oxidase, pro collagen peptidases.
Usually affects type III collagen. Hyper mobility of joints, hyper extensibility of skin, fragility of skin, vascular problems
Marfan Syndrome
Fibrillin-1 mutation (scaffold for elastic fibers)
Long limbs, aractodactyly, lens dislocation, aortic root dialation, pectus excavatum,
GLUT-1 deficiency
RBCs and brain/blood barrier. Encephalopathy.
Cystic fibrosis
CFTR defect. Abc transporter. Cl- channel. Increases fluidity of lungs, pancreatic dicta, GIT, reproductive tracts
MODY-2
Maturity onset diabetes myelitis of the young type 2. Glucokinase deficiency. Inherited diabetes mellitus. Can’t sense high [blood glucose]
Leigh disease
PDH deficiency. Lactic acidosis, up alanine, down accoa, down ATP, neurologic defects, myopathy, fatal early age
Leber’s hereditary optic neuropathy
NADH dehydrogenase deficiency (complex 1)
Mitochondrial myopathies
Learns-sayre
MELAS
MERRF
3-ß hydrosteroid dehydrogenase deficiency
No glucocorticoids mineral corticoids, active androgens or estrogens
increased salt in urine
female like genetalia
17-α-hydroxylase deficiency
no sex hormones or cortisol
increased mineralcorticoids–>up Na+, up fluids, up bp
female-like genetalia
21-α-hydroxylase deficiency
most common form of CAH (partial and complete)
mineralocorticoids and glucocorticoids absent or deficient
over production of androgens leads to masculinization of external genitalia in females, early virilization in males
11-β-hydroxylase deficiency
decrease cortisol, corticosterone, aldosterone
increased deoxycorticosterone–>fluid retention–>suppresses renin/angiotensin system (low renin hypertension)
masculinization and virilization
