Zeng Y T, Ren Z R, Zhang M L, Huang Y, Zeng F Y, Huang S Z
Shanghai Institute of Medical Genetics, Shanghai Children's Hospital, PR China.
J Med Genet. 1993 Aug;30(8):655-7. doi: 10.1136/jmg.30.8.655.
We describe a new point mutation in the SRY gene of a Chinese XY female with gonadal dysgenesis (Swyer syndrome). Using the double stranded DNA cycle sequencing method, a single nucleotide substitution of G-->A was identified at codon 113 of the patient's SRY gene, resulting in a conservative amino acid change from alanine (A) to threonine (T) at a residue that lies within the putative DNA binding motif. With this mutation, one MnlI recognition site is abolished and a new BsmAI site is present in the DNA sequence of the SRY gene; therefore, it is easily detected by analysis of the digestion of the amplified SRY DNA fragment on an electrophoretic agarose gel. In situ hybridisation to the XY female's chromosomes showed that her mutant SRY gene was indeed located on the short arm of her Y chromosome. The SRY mutation in the XY female reported here occurred de novo, as sequence analysis showed that it was not present in her father or other family members.
我们描述了一名患有性腺发育不全（Swyer综合征）的中国XY女性SRY基因中的一个新的点突变。使用双链DNA循环测序方法，在患者SRY基因的第113密码子处鉴定出一个G→A的单核苷酸替换，导致在假定的DNA结合基序内的一个残基处发生从丙氨酸（A）到苏氨酸（T）的保守氨基酸变化。有了这个突变，一个MnlI识别位点被消除，并且在SRY基因的DNA序列中出现了一个新的BsmAI位点；因此，通过分析扩增的SRY DNA片段在琼脂糖凝胶电泳上的消化情况很容易检测到它。对XY女性染色体的原位杂交显示，她的突变SRY基因确实位于她Y染色体的短臂上。这里报道的XY女性中的SRY突变是新发的，因为序列分析表明它在她的父亲或其他家庭成员中不存在。
