[Habitual abortion and high frequency of low frequent X chromosome monosomy mosaicism: detection by interphase FISH analysis of buccal mucosa cells and lymphocytes].

: FISH analysis using X alpha satellite probe was performed to the nuclei of lymphocytes obtained from fourteen women with having a history of habitual abortion for unknown causes(WHA) and from 65 normal control women(NW), in order to determine whether low frequency X monosomy mosaicism is one of the factors of habitual abortion. In parallel, the nuclei of buccal mucosa from 8 of WHA and 65 NW were also examined. Five hundreds of the interphase nuclei in each sample were observed. As results, the frequency of X monosomy in NW found in the lymphocytes or buccal mucosa was ranged from 0-3.2%(mean 1.59%, SD 0.69%) or from 0-3.2%(mean 1.24%, SD 0.85%), respectively. However, the occurrence of X monosomy in WHA was significantly higher compared with that of NW; i.e., 0.8-5.8%(mean 3.21%, SD 1.67) for lymphocytes, and 1.8-7.4%(mean 4.45%, SD 1.73%) for buccal mucosa. These results allowed us to define the reference intervals to discriminate WHA from NW were less than 2.97% or 2.94% for lymphocytes or buccal mucosa, respectively. Based on the reference intervals defined above, the high frequency of X monosomy mosaicism was actually found in 9 of 14 WHA. These results altogether strongly suggested that the low frequency X monosomy mosaicism was one of the factors of habitual abortion.