Q.
Fused ear lobes appear in the progeny due to an autosomal recessive gene. Work out the genotypes of members in the given pedigree.
I-$2$
II-$3$
III-$1$
(a)$\,\,$
$aa\,\,$
$Aa\,\,$
$Aa\,\,$
(b)$\,\,$
$aa\,\,$
$AA\,\,$
$AA\,\,$
(c)$\,\,$
$Aa\,\,$
$Aa\,\,$
$Aa\,\,$
(d)$\,\,$
$aa\,\,$
$Aa\,\,$
$AA\,\,$
| I-$2$ | II-$3$ | III-$1$ | |
|---|---|---|---|
| (a)$\,\,$ | $aa\,\,$ | $Aa\,\,$ | $Aa\,\,$ |
| (b)$\,\,$ | $aa\,\,$ | $AA\,\,$ | $AA\,\,$ | (c)$\,\,$ | $Aa\,\,$ | $Aa\,\,$ | $Aa\,\,$ |
| (d)$\,\,$ | $aa\,\,$ | $Aa\,\,$ | $AA\,\,$ |
Principles of Inheritance and Variation
Solution:
Given pedigree chart for fused ear lobes (autosomal recessive trait) can be explained as follows :
