GB1: D/R Diseases

Question 1

Albinism

Answer 1

• recessive
• genetic mutation affects amount of melanin body produces
• symptoms:
  lack of pigmentation in skin/hair

Question 2

cystic fibrosis

Answer 2

• recessive
• defective/absent chloride transport channels in membrane; buildup of chloride ions outside cell
• symptoms:
  mucus buildup in some internal
  organs, abnormal absorption of nutrients in small intestine
• affects a lot european descent

Question 3

sickle-cell disease

Answer 3

• recessive
• substitution of single amino acid in hemoglobin protein in red blood cells
• homozygous: hemoglobin is abnormal
• symptoms:
  physical weakness, pain, organ
  damage, paralysis

Question 4

Tay-sach’s disease

Answer 4

• recessive
• dysfunctional enzyme causes accumulation of lipids in brain, fatal
• symptoms:
  muscle weakness, developmental delays, vision/hearing loss, startle response
• organismal: allele is recessive
• biochemical: heterozygous - phenotype is incompletely dominant (half of the lipids are being broken down)
• molecular level: heterozygous - alleles are codominant (some enzymes are functioning, others are not)

Question 5

Huntington’s disease

Answer 5

• dominant
• degenerative disease of nervous system
• phenotypic effects show at 35-40 years old, once it starts, fatal

Question 6

achondroplasia

Answer 6

• dominant
• mutation in growth factor gene
• form of dwarfism

Question 7

polydactyly

Answer 7

• dominant
• person has more than normal number of fingers/toes

Question 8

green-red colorblindness/colorblindness in general

Answer 8

• recessive
• X-linked (sex-linked)
• cannot see red/green/or whatever color

Question 9

Hemophilia

Answer 9

• recessive
• X-linked (sex-linked)
• absence of one/more proteins required for blood clotting (clot is slow to form)

Question 10

duchenne muscular dystrophy

Answer 10

• recessive
• X-linked (sex-linked)