Two Heifers with Gonadal Dysgenesis and the Sex Chromosomal Constitution XY

Characterisation of eight cattle with Swyer syndrome by whole‐genome sequencing

“…The underdeveloped reproductive tract observed in the present study is in line with clinical examinations reported elsewhere of Swyer cattle (Chapman et al, 1978;De Lorenzi et al, 2018) albeit others like Henricson and Åkesson (1967) reported a normal sized uterus in their two Swyer Swedish Red and White dairy individuals. Smaller uterine size has also been reported in Swyer humans relative to controls (Michala et al, 2008).…”

“…Consistent with the present study, a flattened ovary has also been documented in an almost 3‐year‐old Swyer Charolais individual (Chapman et al, 1978) albeit only one gonad was detected in that heifer. Elongated, streaked or ‘almond‐shaped’ (Henricson & Åkesson, 1967) gonads is a common feature of cattle with Sywer syndrome (Kondoh et al, 1992; Sharma et al, 1980). Similar to the present study, primordial follicles have been detected on the ovaries of Swyer cattle (Chapman et al, 1978).…”

“…All eight suspected Sywer individuals in the present study were confirmed to have the Swyer condition with seven of the eight not having the SRY gene ( SRY − individuals) and the eighth individual having the SRY gene ( SRY +) with no obvious mutation within. While there has been numerous reports on Swyer syndrome in cattle (Chapman et al, 1978; Hare et al, 1994; Henricson & Åkesson, 1967; Kondoh et al, 1992; Macmillan et al, 1984; Sharma et al, 1980), many of those were before the SRY gene was discovered in 1990 (Sinclair et al, 1990) meaning that the SRY status of the individuals in those studies could not be determined. Kawakura et al (1996) reported on three SRY − cattle from different breeds while De Lorenzi et al (2018) reported on what they described as the first reported case of SRY + in Holstein cattle.…”

“…Several cases of XY sex reversals have been reported in bovines (Chapman et al, 1978; Hare et al, 1994; Kondoh et al, 1992; Macmillan et al, 1984; Sharma et al, 1980) as far back as 1967 (Henricson & Åkesson, 1967). In most cases, the reproductive tract is underdeveloped and ovaries, if present, are usually elongated (Chapman et al, 1978; Henricson & Åkesson, 1967; Kondoh et al, 1992; Sharma et al, 1980). Swyer syndrome has also been reported in a multitude of other species including humans (Khare et al, 2017), horses (Raudsepp et al, 2010), dogs (Whyte et al, 2009), and sheep (Ferrer et al, 2009).…”

“…Swyer syndrome is a rare type of disorder (or difference) of sexual development (DSD) and can also be called testicular feminisation syndrome (Morris, 1953). Several cases of XY sex reversals have been reported in bovines (Chapman et al, 1978; Hare et al, 1994; Kondoh et al, 1992; Macmillan et al, 1984; Sharma et al, 1980) as far back as 1967 (Henricson & Åkesson, 1967). In most cases, the reproductive tract is underdeveloped and ovaries, if present, are usually elongated (Chapman et al, 1978; Henricson & Åkesson, 1967; Kondoh et al, 1992; Sharma et al, 1980).…”