Abnormal Genetics Information about Genetic Abnormalities Inversions, deletions, duplications and translocations are all mutations that can occur in the chromosome. Color blindness and hemophilia are both sex-linked abnormalities that are usually carried on the X chromosome. The mother passes on the abnormality through her X chromosome. Hemophiliacs are missing a clotting factor in their blood due to an X-linked genetic disease.
Trisomy is a term used when an extra chromosome is present.
Individuals with Turners Syndrome have sex chromosomes that are represented as XO because one sex chromosome is missing. Downs Syndrome is caused by a chromosomal mutation in which there is an extra chromosome number 21. Sex-linked abnormalities are usually carried by the mother and are usually passed on to their male offspring. When a boy has color blindness, often the mother carries the trait, but does not have color blindness herself. Genetic counseling is recommended for couples who have genetic abnormalities in their family background.