Balajee A S, Sharma T
Cytogenetics Laboratory, Banaras Hindu University, Varanasi, India.
Cytogenet Cell Genet. 1994;66(2):89-92. doi: 10.1159/000133673.
In situ digestion of metaphase chromosomes with AluI revealed differences in the distribution of Mus musculus-like AT-rich heterochromatin in the complements of the Indian pygmy field mice, M. booduga and M. dunni. In M. booduga, although the banding pattern was almost comparable to that of M. musculus, AluI-resistant bands were much reduced in size at the centromeric regions. In all three chromosome types of the M. dunni complex, M. musculus-like AT-rich heterochromatin was found to be confined mainly to two small segments on the short arm of the X chromosome. This AT-rich heterochromatin varied greatly in both position and quantity in the two X chromosomes. In addition to the polymorphism, a whole block of M. musculus-like AT-rich heterochromatin was found at the centromeric region of an autosome in one individual of M. dunni.
用AluI对中期染色体进行原位消化，揭示了印度侏儒田鼠（短尾侏鼠和邓氏侏鼠）染色体组中类小家鼠富含AT的异染色质分布存在差异。在短尾侏鼠中，虽然带型与小家鼠的几乎相当，但着丝粒区域的AluI抗性带在大小上大幅减小。在邓氏侏鼠复合体的所有三种染色体类型中，发现类小家鼠富含AT的异染色质主要局限于X染色体短臂上的两个小片段。这种富含AT的异染色质在两条X染色体上的位置和数量差异很大。除了多态性外，在一只邓氏侏鼠个体的一条常染色体着丝粒区域发现了一整块类小家鼠富含AT的异染色质。
