SRY Protein<unk> s typically have one X chromosome and one Y chromosome in each diploid cell of their bodies. Females typically have two X chromosomes.<unk> <unk> s that are SRY-positive have two X chromosomes, with one of them containing genetic material (the SRY gene) from the Y chromosome; this gene causes them to develop a<unk>  phenotype despite having chromosomes more typical of females. Some<unk> <unk> s, however, do not have the SRY gene (SRY-negative) and the<unk>  phenotype may be caused by another gene on one of the autosomes. SRY-positive An example of translocation between two chromosomes The SRY gene, normally found on the Y chromosome, plays an important role in sex determination by initiating testicular development. In about 80 percent of<unk> <unk> s, the SRY gene is present on one of the X chromosomes. The condition results from an abnormal exchange of genetic material between chromosomes (translocation). This exchange occurs as a random event during the formation of sperm cells in the affected person's father. The tip of the Y chromosome contains the SRY gene and, during recombination, a translocation occurs in which the SRY gene becomes part of the X chromosome. If a fetus is conceived from a sperm cell with an X chromosome bearing the SRY gene, it will develop as a<unk>  despite not having a Y chromosome. This form of the condition is called SRY-positive 46,XX testicular disorder of sex development. SRY-negative About 20 percent of those with 46<unk>  testicular disorder of sex development do not have the SRY gene. This form of the condition is called SRY-negative 46,XX testicular disorder of sex development. The cause of the disorder in these individuals is often unknown, although changes affecting other genes have been identified. Individuals with SRY-negative 46,XX testicular disorder of sex development are more likely to have ambiguous genitalia than are people with the SRY-positive form. The exact cause of this condition is unknown but it has been proposed that mutations in the SOX9 gene may contribute to this syndrome since SOX9 plays a role in testes differentiation during development. Another proposed cause is mutations to the DAX1 gene, which encodes a nuclear hormone receptor. DAX1 represses masculinizing genes; therefore, if there is a loss of function of DAX1, then testes can develop in an<unk>  individual. Mutations in SF1 and WNT4 genes have also been studied in connection with SRY-negative<unk> .
XX male syndrome
XYY syndrome
XXXY syndrome
XYYY syndrome
XXYY syndrome
XXXXY syndrome
Turner syndrome
XYYYY syndrome