Disease and Disorders Exam 1 Flashcards
1
Q
Progeria
A
- rare, fatal childhood disease characterized by premature aging of the musculoskeletal and cardiovascular systems
- associated with mutation in nuclear lamina gene lamin A which forms a structural component of the inner nuclear membrane
- results in a truncated protein known as progerin
2
Q
Mitochondrial diseases
A
- skeletal muscle fibers are particularly sensitive
- can result from mutation in nuclear or mt DNA, mtDNA has much higher rate of mutation
- symptoms vary greatly b/w individuals
- must reach a threshold of mutant DNA : normal DNA
3
Q
Lysosomal storage diseases
A
- autosomal recessive
- causes abnormal accumulation of substances in cell
- generally affects children and is fatal
4
Q
Tay-Sachs
A
- Deficiency in hexosaminidase A which is found in lysosomes and breaks down ganglioside in the brain
- results in accumulation of ganglioside in the brain and neuronal cell death
- common clinical finding is “cherry-red spot” on the retina
5
Q
Hurler Syndrome
A
- defect in the enzyme alpha-L-iduronidase that is normally found in lysosomes and breaks down GAGs
- results in accumulation of GAGs -> skeletal abnormalities and mental retardation
6
Q
Peroxisomal biogenesis disorders
A
- autosomal recessive disease caused by mutations in peroxins, which normally break down very long chain fatty acids
7
Q
Zellweger syndrome
A
- peroxisomal deficiency
- accumulation of long chain fatty acids leads to impaired brain development, liver and kidney lesions
- usually fatal within first year of life
8
Q
I-cell disease
A
- characterized by defective physical growth and mental retardation
- caused by deficiency in GlcNac-1-phosphotransferase in the golgi
- lysosomal enzymes are not phosphorylated in the golgi and are consequently released form the cell
- leads to accumulation of undegraded proteins
- affected children usually only live for 5-7 yrs
9
Q
Xeroderma Pigmentosum
A
- defect in nucleotide excision repair
- leads to inability to remove UV-damaged bases and an accumulation of mutations
- patients are highly sensitivity to sunlight and usually develop multiple pigmented growths on the skin and have a high risk of developing skin cancer
10
Q
Hereditary Nonpolyposis Colorectal Cancer (Lynch Syndrome)
A
- d/t mutations in either MSH2 or MLH1 resulting in an inability of cells to repair nucleotide mismatches
- affected individuals are at risk of developing a number of cancers, including colorectal
11
Q
Ataxia Telangiectasia
A
- d/t mutation in ATM, which is responsible for recruiting the proteins needed to repair double-stranded DNA breaks
- results in defective NHEJ and homologous recombination repair
- susceptible to agents that cause double stranded breaks (x-rays, radiation therapy)
12
Q
Cystic Fibrosis
A
- d/t mutation in CFTR (member of ABC transporter family)
- CFTR is a Cl- transporter found in the plasma membrane that also can transport bicarb
- is regulated by ATP binding and PKA
13
Q
Kartagener Syndrome
A
- inherited disorder characterized by defective cilia in the respiratory tract, fallopian tubes and sperm flagella
- results in reduced clearance of mucus from lungs and sterility
- d/t mutation in outer dynein arm
- clinical triad: situs inversus (organs are flipped), chronic sinusitis, bronchiectasis
14
Q
Hereditary Spherocytosis
A
- hemolytic anemia characterized by the production of RBCs that are sphere-shaped
- d/t mutations in proteins that make up the RBC cytoskeleton (spectrin, ankyrin, etc)
- RBC destroyed in spleen
15
Q
Ehlers-Danlos Syndrome
A
- Mutation of gene encoding lysyl hydroxylase, responsible for hydroxylating lysines in collagen
- affected individuals have stretchy skin
