Practice question

Because Y chromosome exists exclusively in males under normal karyotype, Y-linked traits manifest solely in male individuals and follow strict paternal lineage inheritance without exception. Daughters do not inherit Y from father, so they never express nor transmit Y-linked trait to next generation. While pedigree might appear to skip generation if affected male has only daughters, generally trait appears in every generation via affected fathers to sons. Unlike autosomal or X-linked traits, no female carriers exist, simplifying recognition of holandric transmission.