Add support for the PAR (pseudo-autosomal region) of the Y chromosome #64
Description
The current implementation enables work with sex chromosome - females have two copies of X chromosome, so they can have allele dosage of 0, 1, or 2, while males have one copy of X, so they can have allele dosage of 0 or 1.
However, we ignore the PAR (pseudo-autosomal region) of the Y chromosome, where males can have allele dosage of 0, 1, or 2.
How could we support this?