Genetics II Flashcards
Cancer of the eye, retina
Retinoblastoma
Mutation in RB1, chromosome 13
Retinoblastoma
Retinoblastoma is due to mutation in gene —- in chromosome —-
Gene RB1, chr 13
This protein, causing retinal cancer, is a regulator of the ——— phase transition. When mutated we cannot stop the transcription factors
G1 to S phase of cell cycle
Hyperphosphorylated Rb
Inactive
Hypophosphorylated Rb
Active
When Rb is not phosphorylated, it is actuve and binds to ——, preventing it from letting the cell to go from —- to —-
ef2, G1 to S
——-++ phosphorylates Rb, thereby it gets inactivated and cannot bind ——
Cyclin dependent kinase K2, ef2 so Ef2 allows cell to go to S phase.
How do you Dx retinoblastoma in a baby?
Look for the RED/ORANGE reflex in his retina, also look for the CORNEAL LIGHT reflex which is a symmetrical reflection. Of the beam of light.
Leukocoria. Deteriorating vision, irritation of the eye, glaucoma, strabismus, enlargement of the eye in advanced cases
Retinoblastoma in children
White appearance of the eye
Leukocoria
Mutation in FB1 gene, chromosome 15
Marfan
Marfan is due to mutation in gene ——- in chromosome ——
Gene FB1, Chromosome 15
Mutation in marfan code for —— glycoprotein
Fibrillin -1, a component of the extra cellular matrix, ECM
What is the role of fibrillin 1 protein?
Stores TGF beta and is essential for the elasticity of the fibers in the body
Thoracic aneurysm or dilated aorta are found in the cardiovascular system of these patients
Marfan
Findings in the lungs of marfan patients
Spontaneous pneumothorax is common
Duran ectasia is common in
Marfan syndrome
Weakening of the connective tissue of Duran sac, painful, lowers quality of life in
Marfan syndrome
Lens dislocation in marfan
Superior - they cannot look down
In lumbar region, the Dúrcal sac weakens and bulges out, causing lower back pain
Dural ectasia
5 disease that look like marfan, marfanoid habitus
Homocystinuria EHlers danlos Congenital contractural arachnodactylia Stickler Syndrome MEN 2b
Inferior subluxation
Homocystinuria
In inferior subluxation, the person cannot look
Up.
Methionine metabolism problem, inferior subluxation, marfanoid habitus, precuts excavatum, scoliosis
Homocystinuria
Lysyl oxidase or procollagen peptidase deficiency
Ehlers danlos
Triad of Men 1
Pituitary adenoma, parathyroid hyperplasia, pancreatic tumor
Triad of Men 2a
Parathyroid hyperplasia, medullary thyroid carcinoma, and pheochromocytoma
Triad in Men 2b
Marfanoid habitus , pheochromocytoma, medullary thyroid carcinoma, and mucosal neuromas
Deficiency (quantitative or qualitative) in type 1 collagen
Osteogenesis imperfecta
Glycine replaced by bulky aa
O.I.
Bone fragility, spinal curvatura, loose joints, por muscle tone, blue sclera , hearing loss
O.I.
What are the veins seen under the blue sclera?
Choroidal veins
Hereditary hemorrhagic telangiectasia
Osler, Weber, Rendu Syndrome
Arteriovenous malformation (tangle f vessels) or telangiectasias in the skin, and mucous membranes of lips, orophraynx, respiratory tract, GI tract, urinary tract, also in liver, brain, or spleen,
Osler Weber rendu syndrome
Tangle of vessels whose rupture leads to epistaxis, GI bleeding and hematuria
Osler Weber rendu Syndrome
A person with many large red spots on the tongue, epistaxis and hematuria. Dx?
Osler Weber rendu Syndrome
Familial hypercholesterolemia mutation gene?chromosome?
LDL R
Chromosome 19
Main findings in familial hypercholesterolemia
Xanthelasma and tendon xanthomas
High risk of atherosclerosis leading to CAD
Familial hypercholesterolemia
Young patient with no atherosclerosis history, but disease in family members. He exercises, does not smoke, his father has stroke at 40. Uncle lost leg to peripheral disease at 43.
Familial hypercholesterolemia
Inheritance of familial hypercholesterolemia
Autosomal dominant