(Questions 3-6) Tay-Sachs disease is lethal disorder caused by a recessive mutat

Question

(Questions 3-6) Tay-Sachs disease is lethal disorder caused by a recessive mutation, in this case at the TS locus in humans. TS/TS and TS/ts genotypes do not show symptoms of the disease; however, by the age of 6 months, ts/ts infants begin to regress, usually dying by the age of five. No cure is known for Tay Sachs Tay-Sachs most commonly strikes people from relatively small, closed societies, specifically those of eastern European Jewish (Ashkenazy Jews) and Louisiana (US) Cajun descent. In the general population, the observed frequency of the ts ALLELE is 0.003 (3 x 10). However, in populations of Ashkenazy Jews and Cajuns, the observed frequency of the ts ALLELE is 10 times greater, or 0.03 (3 x 10). Based on this information, answer the following 4 questions 3. Among the offspring from two parents, both ofwhom are CARRIERS of Tay-Sachs disease, what is the expected fraction of offspring which are carriers, and what it is the expected fraction of offspring which have the disease? a) Carriers: 34; Diseased: a b) Carriers: 0 ; Diseased: c) Carriers: ; Diseased: 0 -5 Cd)Carriers: %; Diseased E) Carriers: %; Diseased:X

Explanation / Answer

3.d. Carriers: 1/2; Diseased: 1/4.

Parents are carriers. Their genotype is TSts.

TSts (no symptoms of disease)

carrier

TSts (no symptoms of disease)

carrier

Out of 4 offsprings 2 are having genotype TSts. They are carriers. One is diseased.

Female Male TS ts TS TSTS (no symptoms of disease)

TSts (no symptoms of disease)

carrier

ts

TSts (no symptoms of disease)

carrier

tsts (diseased)

Related Questions

Navigate

• Browse (All)
• Browse #
• Subjects

---

---

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.