Females Heterozygous for the Recessive Second Chromosome Mutations Pn,px,and Sp

question 47

Essay

Females heterozygous for the recessive second chromosome mutations pn,px,and sp are mated to a male homozygous for all three mutations.The offspring are as follows: $$\begin{array} { | l | r | } \hline p x s p c n & 1,461 \\\hline p x s p + & 3,497 \\\hline p x + c n & 1 \\\hline p x + + & 11 \\\hline + s p c n & 9 \\\hline + s p + & 0 \\\hline + + c n & 3,482 \\\hline + + + & \underline { 1,539 } \\\hline & 10,000 \\\hline\end{array}$$
What is the genotype of the females that gave rise to these progeny?

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Definitions:

Unilineal Kin Group

A social group where membership is inherited through either the male (patrilineal) or female (matrilineal) line exclusively.

Nuclear Families

A family group consisting of parents and their children, regarded as a basic social unit.

Unilineal Descent

Descent traced exclusively through either the male or the female line of ancestry to establish group membership.

Matrilineal Descent

A lineage system where ancestral descent is traced through the mother's line rather than the father's.