Edward syndrome is on account of …….

Polytene chromosomes in salivary glands of are formed as a result of

$A$ : Antlers in male deer are sex influenced traits.
$R$ : These are controlled by autosomal genes which are influenced by the sex of bearer

$A$ : Occasionally mammary glands are functional in males and the condition is called gynaecomastia.

$R$ : Decreased testosterone in later life may also lead to gynaecomastia. It is usually due to perturbation of estrogen to androgen ratio.

The gene which increases the frequency of mutation in other gene is referred to as