In mammals, female development has traditionally been considered a default process in the absence of the testis-determining gene, Sry. Recently, it has been documented that the gene for R-spondin1 (RSPO1), a novel class of soluble activator for Wnt/beta-catenin signaling, is mutated in two Italian families with female-to-male (XX) sex reversal. To elucidate the role of Rspo1 as a candidate fema...

Here, we describe a 3-month-old XX male French Bulldog. The diagnosis was based on the clinical signs, gonadal histology and cytogenetic analysis. Additionally, the dog was confirmed to be Sry negative by semi-quantitative reverse transcription polymerase chain reaction (sqRT-PCR). Canine Sry-negative XX sex reversal is a disorder of gonadal development where individuals who have a female karyo...

The main factor influencing sex determination of an embryo is the sex-determining region Y (SRY), a master regulatory gene located on the Y chromosome. The presence of SRY causes the bipotential gonad to differentiate into a testis. However, some individuals carry a Y chromosome but are phenotypically female (46,XY females) or have a female karyotype but are phenotypically male (46,XX males). 4...

It is now well established that the differentiation of the primitive gonad into the testis during early human embryonic development depends on the presence of the SRY gene. However, the existence of total or partial sex reversal in 46,XX males with genetic mutations not linked to the Y chromosome suggests that several autosomal genes acting in association with SRY may contribute to normal devel...

The sex-determining region of Chr Y (Sry) gene is sufficient to induce testis formation and the subsequent male development of internal and external genitalia in chromosomally female mice and humans. In XX sex-reversed males, such as XX/Sry-transgenic (XX/Sry) mice, however, testicular germ cells always disappear soon after birth because of germ cell-autonomous defects. Therefore, it remains un...

Adult intraspecific mouse chimaeras, derived by introducing male embryonal stem cells into unsexed host blastocysts, were examined to determine whether gonadal sex was correlated with the sex chromosome composition of particular cell lineages. The fertility of XX in equilibrium XY and XY in equilibrium XY male chimaeras was also compared. The distribution of XX and XY cells in 34 XX in equilibr...

The clinical genetics and hormonal status of the 46,XX male is well determined. This is a rare condition that affects one out 20,000 male births. This study evaluates 5 infertile patients with no abnormalities in sex definition in whom we noted variants in their phenotype, like small penis, hypospadias, cryptorchidism, flat scrotum, and in some of them small testis. Only one patient had gynecom...

Differentiation of the bipotential gonad into testis is initiated by the Y chromosome-linked gene SRY (Sex-determining Region Y) through upregulation of its autosomal direct target gene SOX9 (Sry-related HMG box-containing gene 9). Sequence and chromosome homology studies have shown that SRY most probably evolved from SOX3, which in humans is located at Xq27.1. Mutations causing SOX3 loss-of-fu...

An exotic species is a species that is not native to its current habitat and is known as invasive if it negatively impacts this habitat. There have been a variety of attempts to eradicate invasive species in different areas, but they have not been particularly successful. In an effort to find a better method for eradicating invasive fish species, Gutierrez and Teem proposed a method involving s...