Sex-linked trait?

Cleft chin is a cleft linked dominant trait, if a man with a cleft chin marries a woman with a round chin what percent of their female offspring will show the cleft chin trait? 0,25,50,75,100





what percent of the males will show it?


0,25,50,75,100

Sex-linked trait?
Did you mean sex-linked dominant?





The thing with fathers carrying the sex linked dominant trait is that they can only pass it onto their daughters.





100% of the girls will show the trait


0% of the males will show it
Reply:If cleft chin is a sex-linked trait, it usually resides on the X chromosome.





Let X_C be the allele which contributes to cleft chin.


Let X_c be the allele which contributes to a round chin (normal).





The woman has genotype Xc Xc.


All her gametes will have genotype Xc.





The male has genotype XC Y.





Therefore, their offspring will have genotypes XC Xc and Xc Y.


This means all females will show the cleft chin, and none of the males will have cleft chin.