OMIA:000393-9940 : Tetragametic chimerism (including Freemartin) in Ovis aries (sheep)

In other species: dog , horse , pig , red deer , taurine cattle , bighorn sheep , water buffalo

Categories: Reproductive system phene

Mendelian trait/disorder: unknown

Considered a defect: yes

Cross-species summary: This is a type of sex chromosome difference of sexual development (DSD). Tetragametic chimerism is a rare, sex chromosome difference of sex development characterized by the two different haploid sets of maternal and paternal chromosomes and variable phenotype - from normal male or female genitalia, to different degrees of ambiguous genitalia, and often infertility. Also, in the cases of monochorionic dizygotic twins, it can be confined to blood of both twins. [updated from Orphanet : 199310 ] Freemartin or free-martin is an infertile female animal which is the twin of a male animal whose anti-Müllerian hormones affected its development in utero. Genetically the animals are chimeric (microchimerism, XX/XY leukocyte chimerism) - some stem cells from the male twin are received during in utero development via vascular connections between placentas. The condition is mostly reported in ruminants due to their multicotyledonary placenta type. Phene was renamed to 'Tetragametic chimerism' [16/11/2022]

Cite this entry

Nicholas, F. W., Tammen, I., & Sydney Informatics Hub. (2005). OMIA:000393-9940: Online Mendelian Inheritance in Animals (OMIA) [dataset].


Note: the references are listed in reverse chronological order (from the most recent year to the earliest year), and alphabetically by first author within a year.

1998 Szatkowska, I., Udala, J., Baranowski, P., Katkiewicz, M., Stepien, J. :
Two cases of freemartinism in sheep Acta Veterinaria Brno 67:189 ff., 1998.
1997 Lafi, S.Q., Aldarraji, A.M., Hailat, N.Q., Fathalla, M.A. :
Ovine freemartinism Indian Veterinary Journal 74:339-340, 1997.
1996 Szatkowska, I., Switonski, M. :
Evidence on hereditary occurrence of placental anastomoses in heterosexual twins in sheep Hereditas 124:107-110, 1996. Pubmed reference: 8782431.
1990 Cribiu, E.P., Durand, V., Chaffaux, S. :
Frequency of the freemartinism in Booroola-Merino-Darles. Recueil de Medecine Veterinaire 166:919-922, 1990.
1989 Spedding, R.N., Dobson, H. :
Diagnosis of freemartinism in sheep Veterinary Record 124:18-19, 1989. Pubmed reference: 2916299.
1988 Romagnano, A., Tiemann, M., Niar, A., Helie, O., King, W.A. :
[Freemartinism in domestic animals] Medicin veterinaire du Quebec 18:79-84, 1988.
1987 Chaffaux, S., Matejka, M., Cribiu, E.P., Crespeau, F., Eychenne, F., Ricordeau, G. :
[Cytogenetic, anatomical and histological study of two freemartin Romanov ewes] Recueil de Medecine Veterinaire 163:15-21, 1987.
Matejka, M., Cribiu, E.P., Ricordeau, G., Chaffaux, S. :
[Frequency of freemartinism in Romanov ewes] Recueil de Medecine Veterinaire 163:635-638, 1987.
1971 Dain, A :
The incidence of freemartinism in sheep Journal of Reproduction and Fertility 24:91-97, 1971. Pubmed reference: 5099639.
1965 Bertrand, M. :
[Freemartinism] Revue de Medecine Veterinaire 116:575-596, 1965.
Gerneke, W.H. :
Chromosomal evidence of the freemartin condition in sheep - Ovis aries Journal of the South African Veterinary Medical Association 36:99-104, 1965.

Edit History

  • Created by Frank Nicholas on 06 Sep 2005