X monosomy in a Virilized Female Cat

Abstract

An infertile Siamese female cat was subjected for clinical, histological, cytogenetic and molecular studies due to ambiguous external genitalia (vulva, vagina, rudimentary penis and scrotum-like structure) and masculine behaviour. An elevated oestrogen activity and a detectable level of testosterone were found. The cat underwent laparotomy. The gonads and the uterus were removed and subjected for histological studies, which showed ovaries with corpora lutea and a some primordial follicles. Chromosome studies of lymphocyte and fibroblast cultures, with the use of Giemsa staining, G-banding and whole X chromosome painting by fluorescence in situ hybridization, revealed pure X monosomy. Molecular analysis showed the absence of the SRY gene. Our study revealed for the first time that X monosomy in cats may be associated with virilization, in spite of the lack of the SRY gene.

Disorders of sex development in cats with different complements of sex chromosomes

“…This type of abnormality has mainly been diagnosed in tortoiseshell and calico males, heterozygous at the X-linked orange locus (Pedersen, Berg, Almstrup, & Thomsen, 2014). Recently, several cases of DSD cats with other abnormalities were diagnosed, including a nonmosaic X monosomy (Szczerbal, Nizanski, et al, 2015), mosaicism 37,X/38,XY (Balogh et al, 2015), translocation between X and Y chromosomes (Szczerbal, Stachowiak, Dzimira, Sliwa, & Switonski, 2015) and mosaicism with a cell line carrying a ring Y chromosome-37,X/38,X,r(Y) (Szczerbal et al, 2017). These findings suggest that sex chromosome abnormalities in cats are quite common and are not only restricted to XXY trisomy.…”

Chromosome Abnormalities in Domestic Animals as Causes of Disorders of Sex Development or Impaired Fertility

“…Application of whole X chromosome painting probe facilitated identification of a single X chromosome. For details, see Szczerbal et al [50].…”

Invited Speakers

“…That is due to the fact that the locus of This type of abnormality is called Turner syndrome in humans. We reported a rare case of X monosomy in a female cat with virilized external genitalia (enlarged clitoris) and presence of uterus and ovotesticular tissue(25). In dogs X monosomy was reported more frequently, often in a form of X/XX mosaicism (presence of 77,X and 78,XX cell lines).…”