<unk>  (YCM) is a family of genetic disorders caused by missing genes in the Y chromosome. Many men with YCM exhibit no symptoms and lead normal lives. It is present in a significant number of men with reduced fertility. Reduced sperm production varies from oligozoospermia, significant lack of sperm, or azoospermia, complete lack of sperm.
Y chromosome microdeletion
Chromosome 2q deletion
Chromosome 15q trisomy
Distal trisomy 10q
XY gonadal dysgenesis
Chromosomal deletion syndrome
Tetrasomy 18p
Small supernumerary marker chromosome