Give one factor that can increase sensitivity to sunlight is genetics.

Melanin pigmentation

Explanation:

Pigmentation has a high heritability but susceptibility to cancer of the skin, a key marker to sensitivity is less heritable while melanin is a broad term for a group of natural pigment found in most organisms. it's produced through a multistage chemical process called melanogenesis where the oxidation of amino acid tyrosine is followed by polymerization