sex-linked disorders

conditions produced because the GENES controlling certain characteristics are carried on the SEX CHROMOSOMES , usually the X-CHROMOSOME . Some result from an abnormal number of chromosomes, e.g. KLINEFELTER'S SYNDROME affecting only men, and TURNER'S SYNDROME affecting only women. Other disorders, such as HAEMOPHILIA , are carried on the X-chromosome and these manifest themselves in men because, although the genes are RECESSIVE , there is no other X-chromosome to mask the recessive type, as is the case with women.