Question

The genes, which remain confined to differential region of Y – chromosome, are
1) autosomal genes
2) holandric genes
3) completely sex – linked genes
4) mutant genes

Answer 1

Holandric genes
1. Most of the X and Y are not homologous, however, and undergo NO CROSSING OVER. Traits coded on this DIFFERENTIAL regions of the X and Y exhibit inheritance patterns that are quite different from those shown by autosomal genes, and may be
1. X-linked (located on the differential region of the X chromosome)
2. Y-linked (located on the differential region of the Y chromosome).
3. Y-linked traits, which exist only in males, are known as HOLANDRIC traits. Under normal circumstances, females never express them.