Suppose we have three linked genes, all of which control different aspects of th

Question

Suppose we have three linked genes, all of which control different aspects of the same phenotype (such as one controlling shape, another controlling color, and so forth) We perform a testcross of a triple heterzygote (a+b+c+/a b c) with a triply homozygous recessive (a b c/a b c), and then count the number of progeny in each of the phenotypic classes. There are a total of 550 progeny. Arrange the genotype in the table. Determine order of genes__________________

Given information
genotype of gamete from heterozygous parent Number
a+b+c+, 200
a b+ c+, 66
a+b c+, 19
a b c+, 5
a b c, 180
a+ b c, 54
a b+ c. 20
a+ b+ c 6

Table
Genotype of gamete from heterozygous parent Number Origin

Explanation / Answer

According to the data given in table-
the order of genes is "a c b"
because, recombination freq of a allele is maximum hence its distance is maximum from allele b and c.
recombination freq of c alleles is lowest, suggesting it is present in-between the two other gene because probability of double recombination is very low

recombination freq of b is intermediate

hence gene map is

a-----------------------c-------b

Related Questions

Navigate

• Browse (All)
• Browse S
• Subjects

---

---

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