Term
| Duchenne Muscular Dystrophy |
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Definition
- sex linked
- affects 1 in 3,500 males
- characterized by a progressive weakening of the muscles and loss of coordination
- affected males rarely live past their 20s |
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Term
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Definition
- recessive
- disproportionately high rate of disease among Ashkenazic Jews
- fatal
- causes damage to the nervous system
- dysfunctional enzyme causes an accumulation of brain lipids
- Defective gene on chromosome 15 |
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Term
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Definition
- recessive
- Affects 1:400 African-Americans
- Caused by the substitution of a single amino acid in the hemoglobin protein in red blood cells
- Symptoms include physical weakness, pain, organ damage, and paralysis
- Incompletely Dominant --> heterozygotes have both normal and sickle-cell hemoglobins
- a single copy of the sickle-cell allele found in heterozygotes reduces the frequency and severity of malaria |
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Term
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Definition
- recessive
- Most common (lethal) genetic disease in the US
- 1:2,500 people of European descent
- Allele results in defective or absent chloride transport channels in plasma membranes
- Symptoms: mucus buildup in some
internal organs and abnormal absorption of nutrients in the small intestine |
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Term
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Definition
- dwarfism
- dominant
- the recessive allele is much more common than the dominant allele |
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Term
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Definition
- dominant
- late onset
- degenerative disease of the nervous system
- fatal |
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Term
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Definition
- dominant
- extra digits on the appendages (extra fingers/toes)
- effects 1 in 400 americans |
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Term
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Definition
- an extra X chromosome in a male (XXY)
- male sex organs but abnormally small testes and the man is sterile |
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Term
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Definition
- females with three X chromosomes
- healthy and can not be distinguished from XX females |
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Term
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Definition
- turner syndrome
- phenotypically female
- sterile b/c sex organs do not develop |
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Term
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Definition
- sex linked recessive
- defined by the absence of one or more of the proteins required for blood clotting
- |
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Term
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Definition
- sex linked
- any male with the recessive allele will be color blind |
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Term
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Definition
1. Achondropalasia (dwarfism)
2. Huntington's Disease
3. Polydactyly
- dominant alleles that cause lethal diseases are much less common than recessive diseases that do so
- dominant lethal alleles can escape elimination if they cause death at a relatively advanced age (allows the allele to be passed on) <-- huntington's |
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Term
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Definition
- show up only in homozygous individuals who inherit one recessive allele from each parent
- usually born to two heterozygous individuals who are carriers but are unaffected
- not evenly distributed among all groups of humans
examples: Tay-Sachs, Cystic Fibrosis, Sickle-Cell |
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Term
| Incompletely Dominant Disorders |
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Definition
- At the organismal level, the normal allele is incompletely dominant
- Heterozgotes are usually healthy but may suffer some symptoms of the disease
example: sickle-cell disease |
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Term
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Definition
- diseases that have a genetic component plus a significant environmental influence
- effects a much larger portion of the population than hereditary diseases
examples: heart disease, diabetes, cancer, alcoholism, schizophrenia |
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Term
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Definition
1. Color Blindness
2. Hemophilia
3. Duchenne Muscular Dystrophy |
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Term
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Definition
- Down Syndrome
- effects 1 out of 700 US children
- the result of an extra chromosome 21
- includes characteristic facial features, short stature, heart defects, susceptibility to respiratory infection, mental retardation
- shorter life span
- most are sterile
- correlation with maternal age (the older the mother, the higher the risk) |
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