In this study, we describe an eighteen-month-old Holstein–Friesian heifer with a deformed vulva, located abdominally. The heifer showed typical signs of estrus. A comprehensive anatomical and histopathological examination revealed a blind-ended vagina and an additional section of urethra, which became a part of the shortened penis. Cytogenetic analysis showed the presence of two cell lines: 60,XX and 90,XXY. The frequency of the triploid cell line was low (3%) in leukocytes and elevated (35%) in fibroblasts. The molecular detection of Y-linked genes (SRY and AMELY) in the blood, skin, hair follicles, and buccal epithelial cells confirmed the presence of a cell line carrying the Y chromosome. Genotyping of 16 microsatellite markers in DNA isolated from hair follicles and fibroblast culture showed the presence of one (homozygous) or two variants (heterozygous) at all the studied loci, and allowed chimerism to be excluded. We concluded that the heifer had diploid/triploid (60,XX/90,XXY) mosaicism. To our knowledge, this is only the fifth such case to be reported worldwide in this species. Since cytogenetic studies are routinely performed on in vitro cultured leukocytes, we suspect that the prevalence of this chromosome abnormality is underestimated, as it is known from published reports that the frequency of the triploid cell line is usually very low in leukocytes.

中文翻译：

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患有罕见马赛克的荷斯坦–弗里斯兰小母牛的性发育障碍（60，XX / 90，XXY）：遗传，解剖学和组织学研究

在这项研究中，我们描述了一个18个月大的荷斯坦-弗里斯兰小母牛，其外阴畸形位于腹部。小母牛表现出典型的发情迹象。全面的解剖和组织病理学检查显示，盲端的阴道和尿道的另一部分成为了缩短的阴茎的一部分。细胞遗传学分析显示存在两种细胞系：60，XX和90，XXY。三倍体细胞系的频率在白细胞中较低（3％），在成纤维细胞中较高（35％）。Y连锁基因的分子检测（SRY和AMELY）在血液，皮肤，毛囊和颊上皮细胞中证实存在携带Y染色体的细胞系。从毛囊和成纤维细胞培养物中分离的DNA中的16种微卫星标记的基因分型显示，在所有研究的基因座处均存在一个（纯合）或两个变体（杂合），并排除了嵌合现象。我们得出的结论是，小母牛具有二倍体/三倍体（60，XX / 90，XXY）镶嵌。据我们所知，这只是全世界该物种中第五例此类病例。由于细胞遗传学研究通常是在体外培养的白细胞上进行的，因此我们怀疑这种染色体异常的发生率被低估了，正如从已发表的报道中得知的那样，三倍体细胞系的频率通常在白细胞中非常低。