Tafsir of Al-Infitar 82:8

In whatever form He willed, He put you together. Mujahid said, "In which resemblance: the father, the mother, the paternal uncle, or the maternal uncle.'' In the Two Sahihs it is recorded from Abu Hurayrah that a man said, "O Messenger of Allah! Verily, my wife has given birth to a black boy.'' The Prophet said,

هل لك من إبل

Do you have any camels? The man said, "Yes.'' The Prophet then said,

فما ألوانه

What color are they? The man said, "Red.'' The Prophet said,

فهل فيها من أورق

Do any of them have patches of gray? The man said, "Yes.'' The Prophet asked him,

فٲنى أتاها ذلك

How did this happen to them? The man replied, "It is probably an inherited genetical strain.'' The Prophet then said,

وهذا عسى أن يكون نزعه عرق

Likewise, this (with your son) is probably an inherited genetical strain. Concerning Allah's statement,

كﻼ بل تكذبون بالدين