Page D C, Brown L G, de la Chapelle A
Nature. 1987;328(6129):437-40. doi: 10.1038/328437a0.
In most human 'XX males', DNA sequences normally found on Yp, the short arm of the Y chromosome, are present on Xp, the short arm of the X chromosome. To establish whether this transfer involves a terminal portion of Yp, and whether a terminal portion of Xp is lost in the process, we followed the inheritance of pseudoautosomal restriction fragment length polymorphisms in two XX-male families. One XX male apparently inherited the entire pseudoautosomal region of his father's Y chromosome and no part of the pseudoautosomal region of his father's X chromosome. The second XX male also inherited the entire pseudoautosomal region of his father's Y, but in addition inherited a proximal portion of the pseudoautosomal region of his father's X. These findings argue that XX males result from the transfer of a terminal portion of Yp onto Xp in exchange for a terminal portion of Xp (ref. 7). This implies that the testis-determining factor gene (TDF) maps distally in the strictly sex-linked portion of Yp, near the pseudoautosomal domain. The XX males described here appear to result from single (and, at least in the second case, unequal) crossovers proximal to the pseudoautosomal region on Yp and proximal to or within the pseudoautosomal region on Xp.
在大多数人类“XX男性”中，通常位于Y染色体短臂Yp上的DNA序列出现在X染色体短臂Xp上。为了确定这种转移是否涉及Yp的末端部分，以及在此过程中Xp的末端部分是否丢失，我们追踪了两个XX男性家族中拟常染色体限制性片段长度多态性的遗传情况。一名XX男性显然继承了其父亲Y染色体的整个拟常染色体区域，而未继承其父亲X染色体拟常染色体区域的任何部分。第二名XX男性同样继承了其父亲Y染色体的整个拟常染色体区域，但另外还继承了其父亲X染色体拟常染色体区域的近端部分。这些发现表明，XX男性是由于Yp的末端部分转移到Xp上，以换取Xp的末端部分所致（参考文献7）。这意味着睾丸决定因子基因（TDF）定位于Yp严格性连锁部分的远端，靠近拟常染色体区域。此处描述的XX男性似乎是由Yp上拟常染色体区域近端以及Xp上拟常染色体区域近端或内部的单次（至少在第二种情况下为不等位）交叉所致。
