Washburn L L, Eicher E M
Jackson Laboratory, Bar Harbor, Maine 04609.
Genetics. 1989 Sep;123(1):173-9. doi: 10.1093/genetics/123.1.173.
We previously described a locus on chromosome (Chr) 17 of the mouse that is critical for normal testis development. This locus was designated "T-associated sex reversal" (Tas) because it segregated with the dominant brachyury allele hairpin tail (Thp) and caused gonads of C57BL/6J XY, Thp/+ individuals to develop as ovaries or ovotestes rather than as testes. To clarify the inheritance of Tas, we investigated the effects of T-Orleans (TOrl), another brachyury mutation, on gonad development. We found that gonads of C57BL/6J XY, Thp/+ and TOrl/+ mice develop ovarian tissue if the Y chromosome is derived from the AKR/J inbred strain, whereas normal testicular development occurs in the presence of a Y chromosome derived from the C57BL/6J inbred strain. From these observations we conclude that: (1) Tas is located in a region on Chr 17 common to the deletions associated with Thp, and TOrl, and (2) the Y-linked testis determining gene, Tdy, carried by the AKR/J inbred strain differs from that of the C57BL/6J inbred strain. We suggest that in mammals Tdy is not the sole testis determinant because autosomal loci must be genetically compatible with Tdy for normal testicular development.
我们之前描述过小鼠17号染色体（Chr）上的一个位点，它对正常睾丸发育至关重要。这个位点被命名为“T相关性反转”（Tas），因为它与显性短尾等位基因发夹尾（Thp）连锁，并且导致C57BL/6J XY、Thp/+个体的性腺发育为卵巢或卵睾，而非睾丸。为了阐明Tas的遗传情况，我们研究了另一个短尾突变T-奥尔良（TOrl）对性腺发育的影响。我们发现，如果Y染色体源自AKR/J近交系，C57BL/6J XY、Thp/+和TOrl/+小鼠的性腺会发育出卵巢组织，而当存在源自C57BL/6J近交系的Y染色体时，则会发生正常的睾丸发育。基于这些观察结果，我们得出以下结论：（1）Tas位于Chr 17上与Thp和TOrl相关的缺失所共有的区域，并且（2）AKR/J近交系携带的Y连锁睾丸决定基因Tdy与C57BL/6J近交系的不同。我们认为，在哺乳动物中，Tdy不是唯一的睾丸决定因素，因为常染色体位点必须与Tdy在基因上兼容，才能实现正常的睾丸发育。
