Hereditary Disorders Flashcards
(13 cards)
What is Hemophilia?
Deficiency of antihemophilic globulin protein required for normal blood coagulation
Carrier females appear normal but can pass normal or defective gene to offspring. Males who inherit the defective gene have the disease. More prevalent in men than women.
What are the two genes involved in Congenital Polycystic Kidney Disease?
PKD1 and PKD2
Mutations in these genes lead to disturbed proliferation of tubular epithelial cells.
What characterizes Achondroplasia?
Type of dwarfism in which limbs are disproportionally short
Caused by mutation in FGFR3 gene involved in converting cartilage to bone.
What are Autosomal Dominant Disorders?
Mutations that are permanent changes in genetic material
Can arise spontaneously or due to exposure to radiation, certain chemicals, or viruses. They can be passed on to offspring.
What can mutations that induce minor changes in protein structure cause?
Serious changes in cell function
Example: Sickle cell anemia.
What are Genetically Transmitted Diseases?
Abnormalities of individual genes on chromosomes
Chromosomes appear normal and may arise spontaneously or due to environmental teratogens.
What is the mechanism of Phenylketonuria (PKU)?
Some phenylalanine is converted to phenylpyruvic acid
Does not require phenylalanine hydroxylase, leading to build-up in blood and urine, causing permanent mental damage.
What is the prevalence of Sickle Cell Disease (SCD) in African Americans attributed to?
Evolutionary response to Malaria
Found predominantly in persons of African descent.
What is Phenylalanine and its significance?
Essential amino acid present in dietary protein
Converted to tyrosine to make thyroid hormone, melanin, etc.
What causes Cystic Fibrosis?
Defective chloride ion transporter gene (CFTR)
Results in dysfunction in mucous and sweat glands, leading to viscous mucous secretions and recurrent lung infections.
What is Tay-Sachs Disease caused by?
Lack of lysosomal enzyme (hexosaminidase A)
Leads to accumulation of lipids in nerve cells in the brain and ANS, with onset at 6 months and death by 3-4 years.
What mutation causes Sickle Cell Anemia?
Mutation in hemoglobin gene (A hemoglobin = normal)
Sickle (S) hemoglobin = mutant, leading to changes in hemoglobin when blood oxygen is low.
What is the difference between heterozygote and homozygote in Sickle Cell Anemia?
Heterozygote has equal amount of normal and sickle hemoglobin; homozygote has no normal hemoglobin
Homozygote condition results in Sickle Cell Anemia.
