Aetiology of intersexuality in female (XX) pigs, with novel molecular interpretations

Hunter, Richard

doi:10.1002/(sici)1098-2795(199611)45:3<392::aid-mrd17>3.0.co;2-0

Cited by 10 publications

(2 citation statements)

References 50 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…This asymmetry can be observed very early during the gonadal development of birds, because the colonization of the gonadal anlage by primordial germ cells (PGCs) is already asymmetrical with a higher number of PGCs found in the left gonad [30] . Apart from birds, a few reports also describe a LR gonadal asymmetry in some mammals [31] , [32] , amphibians and reptiles (reviewed in [33] ). In teleosts, a LR gonadal asymmetry was observed during gonadal differentiation in Argentine silverside, Odontesthes bonariensis [34] and also during gonadal development in brown trout, Salmo trutta [35] .…”

Section: Discussionmentioning

confidence: 99%

High Temperature Increases the Masculinization Rate of the All-Female (XX) Rainbow Trout “Mal” Population

et al. 2014

View full text Add to dashboard Cite

Salmonids are generally considered to have a robust genetic sex determination system with a simple male heterogamety (XX/XY). However, spontaneous masculinization of XX females has been found in a rainbow trout population of gynogenetic doubled haploid individuals. The analysis of this masculinization phenotype transmission supported the hypothesis of the involvement of a recessive mutation (termed mal). As temperature effect on sex differentiation has been reported in some salmonid species, in this study we investigated in detail the potential implication of temperature on masculinization in this XX mal-carrying population. Seven families issued from XX mal-carrying parents were exposed from the time of hatching to different rearing water temperatures ((8, 12 and 18°C), and the resulting sex-ratios were confirmed by histological analysis of both gonads. Our results demonstrate that masculinization rates are strongly increased (up to nearly two fold) at the highest temperature treatment (18°C). Interestingly, we also found clear differences between temperatures on the masculinization of the left versus the right gonads with the right gonad consistently more often masculinized than the left one at lower temperatures (8 and 12°C). However, the masculinization rate is also strongly dependent on the genetic background of the XX mal-carrying families. Thus, masculinization in XX mal-carrying rainbow trout is potentially triggered by an interaction between the temperature treatment and a complex genetic background potentially involving some part of the genetic sex differentiation regulatory cascade along with some minor sex-influencing loci. These results indicate that despite its rather strict genetic sex determinism system, rainbow trout sex differentiation can be modulated by temperature, as described in many other fish species.

show abstract

Section: Discussionmentioning

confidence: 99%

High Temperature Increases the Masculinization Rate of the All-Female (XX) Rainbow Trout “Mal” Population

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Depletion of the spermatogenic cells might result from hyperthermia due to the pelvic location of the testes or failure of germ cells to remain in primitive seminiferous tubules. According to a previous study, majority of true hermaphrodites in pigs are of XX karyotype with various degrees of masculinization, and lack of the Y chromosome containing the sex determining SRY gene [3,5]. This observation may be explained by translocation or loss of Y chromosome, autosomal mutation, and duplication of the X chromosome, resulting in XX karyotype but retaining a functional Y-chromosomal fragment such as the SRY gene [9,14].…”

mentioning

confidence: 99%

Histological and Genetic Characterization of True Hermaphroditism in Korean Pigs

Lee

Park

et al. 2013

J. Vet. Med. Sci.

View full text Add to dashboard Cite

ABSTRACT. True hermaphrodites are animals of equivocal sex in which both male and female gonads develop simultaneously in the same individual. The frequency of true hermaphroditism is relatively higher in pigs than in other domestic animals. Two Korean pigs were diagnosed with true hermaphroditism showing ovotestes, epididymides, a penis and uteri. The testicular tissues consisted of Sertoli cells that were devoid of spermatogenic cells and showed proliferation of interstitial cells. However, uteri looked normal and had well-developed endometrial glands. Samples showed the interpretation of 38, XX female karyotype and sex-determining region Y (SRY) gene expression was negative. These findings could be helpful to understand true porcine hermaphroditism for animal research as well as for the industry of Korean domestic animals.

show abstract

Sexual differentiation of gonads as a function of temperature in the turtleEmys orbicularis: Endocrine function, intersexuality and growth

et al. 1998

View full text Add to dashboard Cite

Emys orbicularis is a freshwater turtle with temperature-dependent sex determination. Estrogens play a major role in gonadal differentiation; when they are produced at high levels during the thermosensitive period (TSP), ovaries differentiate; when their synthesis is very low, testes differentiate. Estrogens are synthesized from androgens through the activity of aromatase. We examine here two aspects of gonadal differentiation, intersexuality and growth, in E. orbicularis. For gonadal intersexuality, we studied the relationship between gonadal aromatase activity and gonadal structure at 28.5°C (pivotal temperature), from the beginning of TSP to hatching, and compared results to those obtained at 30°C (producing 100% females) and 25°C (producing 100% males). At 28.5°C, both males and females are obtained. However, histological differentiation of gonads is delayed compared to that at 25°C and 30°C, and an ovarian-like cortex of various thicknesses often develops at the surface of the male gonads; thus, several individuals display ovotestes at hatching. Despite important individual variations, the aromatase activity in ovaries differentiating at 28.5°C increases during development as in ovaries differentiating at 30°C. In most cases, however, activity is slightly lower than at 30°C, and at the end of embryonic life, it becomes similar to that at 30°C. In testes or ovotestes differentiating at 28.5°C, aromatase activity remains low but is generally slightly higher than in testes at 25°C; however, at the end of embryonic development, it becomes similar to that at 25°C. Oocytes in the cortex of ovotestes begin to degenerate around hatching and continue to degenerate after hatching. Therefore, ovotestes evolve as testes. However, some oocytes may persist at the surface of testes up to the adult age.To estimate gonadal growth, the protein content was measured at different embryonic stages at 25°C and at 30°C. Testis growth is fast during TSP, somewhat slower after TSP, and decreases around hatching. Ovary growth is much slower than testis growth during TSP and then accelerates up to the end of embryonic development. This differential growth is well correlated with gonadal aromatase activity-much higher at 30°C than at 25°C-and can be explained by the fact that during TSP, testicular cords develop at 25°C whereas they are inhibited at 30°C; the ovarian cortex begins to form during this period but grows chiefly after TSP.Both inhibition of testicular cord development and stimulation of cortex development are under the control of endogenous estrogens. In the case of ovotestes, slight increases in estrogen synthesis, compared to that in typical testes, are sufficient to induce the transient formation of an ovarian-like cortex although they do not inhibit the development of testicular cords.

show abstract

Aetiology of intersexuality in female (XX) pigs, with novel molecular interpretations

Cited by 10 publications

References 50 publications

High Temperature Increases the Masculinization Rate of the All-Female (XX) Rainbow Trout “Mal” Population

High Temperature Increases the Masculinization Rate of the All-Female (XX) Rainbow Trout “Mal” Population

Histological and Genetic Characterization of True Hermaphroditism in Korean Pigs

Sexual differentiation of gonads as a function of temperature in the turtleEmys orbicularis: Endocrine function, intersexuality and growth

Contact Info

Product

Resources

About