Y-linkage: The presence of a gene on the Y chromosome. Y-linkage is analogous to X-linkage (the presence of a gene on the X chromosome) in that it says a gene is on one of the sex chromosomes.

It has often been said that little is known about Y-linkage. This is no longer true. As of the year 2000, a number of genes were known to be Y-linked including:

• ASMTY (which stands for acetylserotonin methyltransferase),
• TSPY (testis-specific protein),
• IL3RAY (interleukin-3 receptor),
• SRY (sex-determining region),
• TDF (testis determining factor),
• ZFY (zinc finger protein), PRKY (protein kinase, Y-linked),
• AMGL (amelogenin),
• CSF2RY (granulocyte-macrophage colony-stimulating factor receptor, alpha subunit on the Y chromosome),
• ANT3Y (adenine nucleotide translocator-3 on the Y),
• AZF2 (azoospermia factor 2),
• BPY2 (basic protein on the Y chromosome),
• AZF1 (azoospermia factor 1),
• DAZ (deleted in azoospermia),
• RBM1 (RNA binding motif protein, Y chromosome, family 1, member A1),
• RBM2 (RNA binding motif protein 2) and
• UTY (ubiquitously transcribed TPR gene on Y chromosome).