In: Biology
2. In panthers, black coat (g) is recessive to golden coat (G), pink eyes (b) is recessive to blue eyes (B), and short tail (l) is recessive to long tail (L). A female heterozygous for all three genes is test crossed to a homozygous recessive male and the following offspring were obtained: BGL 70 BgL 78 bGL 358 BGl 4 bgL 8 Bgl 344 bGl 70 bgl 68 a. How many genes are linked? b. Which groups are the parentals? c. What do the other groups represent? d. What is the correct gene order? e. What are the distances between all of the linked genes? f. What is the coefficient of coincidence? g. What is the interference value? What does it mean?
Answer-
a) all three genes (B, G, L) are linked.
b) bGL (=358), Bgl (=344) are parental
c) BGL and bgl are single crossover products between b and g
BgL and bGl are single crossover products between g and l
bgL and BGl are double crossover products.
d) Correct gene order is BGL
e) map distance between b and g =15 mu; g and l = 16 mu
f) coefficient of coincidence (c) is 0.5
g) Interference is 0.5
The explanation is given below: