Pedigree analysis of a Y-linked trait
Y-linked traits never occur in females, and occur in all male descendants of an affected male.
The
concepts of dominant and recessive do not apply to Y-linked
traits, as only one allele (on the Y) is ever
present in any one (male) individual.
Males with a single Y- or X-linked allele are described as hemizygotes, because only one allele is present.
Males with a single Y- or X-linked allele are described as hemizygotes, because only one allele is present.