Gene mapping studies confirm the homology between the platypus X and echidna X1 chromosomes and identify a conserved ancestral monotreme X chromosome

Y染色體

Y染色體是属于XY性別決定系統的大多數哺乳动物（包括人类）的两条性染色體之一. 在哺乳动物的Y染色体中含有的SRY基因能觸發睪丸的生长，并由此決定雄性性狀. 人类的Y染色体中包含约6千万个碱基对.

كروموسوم واي

Χρωμόσωμα Υ

Y-хромосома

Y chromosome

The Y chromosome is one of two sex chromosomes (allosomes) in therian mammals, including humans, and many other animals.