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Updated: Aug 13, 2026
16:19
Fluorescence in situ hybridization (FISH) Protocol in Human Sperm
Published on: September 1, 2009
Abnormalities of human sex determination
1Cambridge University, Department of Pathology, UK.
Journal of Inherited Metabolic Disease
|January 1, 1992
Summary
The SRY gene is a key testis determining factor (TDF), crucial for male sex determination. However, some individuals with male traits lack SRY, suggesting an alternative X-linked gene, TDF-2, may be involved.
Area of Science:
- Genetics
- Developmental Biology
- Molecular Biology
Background:
- Abnormalities of sex determination are investigated through cytogenetic and molecular studies.
- The primary testis determining factor (TDF) is crucial for male development.
- The SRY gene, located on the Y chromosome, is a strong candidate for TDF.
Purpose of the Study:
- To investigate the role of the SRY gene in sex determination.
- To explore alternative genetic factors involved in male differentiation.
- To understand the genetic basis of sex reversal in XY and XX individuals.
Main Methods:
- Isolation and characterization of the SRY gene.
- Analysis of SRY gene mutations in sex-reversed individuals.
- Investigating SRY homologues in animal models (murine).
- Postulating the role of an X-linked gene (TDF-2) in SRY-negative cases.
Main Results:
- SRY gene expression in embryonic gonads and its conservation across mammals.
- Mutations in SRY's conserved domain found in 10% of sex-reversed XY females.
- Murine SRY induced sex reversal in XX embryos.
- Most XX true hermaphrodites and some XX sex-reversed males lack SRY despite testicular differentiation.
Conclusions:
- SRY is a critical testis determining factor, but not the sole determinant.
- An X-linked gene, TDF-2, is postulated to play a role in male differentiation in SRY-negative cases.
- Disruption of TDF-2 may contribute to the female phenotype in XY individuals with Xp duplications.
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