Mutational analysis of SRY: nonsense and missense mutations in XY sex reversal
- 164 Downloads
XY females (n=17) were analysed for mutations in SRY (sex-determining region Y gene), a gene that has recently been equated with the testis determining factor (TDF). SRY sequences were amplified by the polymerase chain reaction (PCR) and analysed by both the single strand conformational polymorphism assay (SSCP) and DNA sequencing. The DNA from two individuals gave altered SSCP patterns; only these two individuals showed any DNA sequence variation. In both cases, a single base change was found, one altering a tryptophan codon to a stop codon, the other causing a glycine to arginine amino acid substitution. These substitutions lie in the high mobility group (HMG)-related box of the SRY protein, a potential DNA-binding domain. The corresponding regions of DNA from the father of one individual and the paternal uncle of the other, were sequenced and found to be normal. Thus, in both cases, sex reversal is associated with de novo mutations in SRY. Combining this data with two previously published reports, a total of 40 XY females have now been analysed for mutations in SRY. The number of de novo mutations in SRY is now doubled to four, adding further strength to the argument that SRY is TDF.
KeywordsCodon Tryptophan Missense Mutation Amino Acid Substitution High Mobility Group
Unable to display preview. Download preview PDF.
- Lopez-Galindez C, Lopez JA, Melero JA, Fuente L de la, Marinez C, Ortin J, Perucho M (1988) Analysis of genetic variability and mapping of point mutations in influenza virus by the RNase A mismatch cleavage method. Proc Natl Acad Sci USA 83:6045–6047Google Scholar
- Orita M, Suzuki Y, Sekiya T, Hayashi K (1989) Rapid and sensitive detection of point mutations and DNA polymorphisms using the polymerase chain reaction. Genomics 8:874–879Google Scholar
- Sambrook J, Fritsch EF, Maniatis T (1989) Molecular cloning: a laboratory manual, 2nd edn. Cold Spring Harbor Laboratory, Cold Spring Harbor, NYGoogle Scholar