Robertsonian translocation is a rare autosomal-dominant genetic chromosomal aberration of female dogs characterized by only 77 chromosomes (normally 78), ambiguous external genitalia and infertility.
Robertsonian translocation involves the centric fusion of two acrocentric chromosomes, usually involving chromosome 23, and is the most common chromosomal translocation reported in dogs.
Affected bitches usually present with female-to-male sex reversal, with 2 normal X chromosomes and a lack of a number of Y chromosome-linked genes. Although female genitalia may be present, vulvar narrowing and clitoral hypertrophy is usually evident, as well as the presence of testes or ovotestes. Spontaneous, first-trimester abortions, frequently reported in humans, does not appear to occur in canine patients.
Infertility is usually a feature of this condition, but heterozygous carriers may still be fertile and produce normal offspring.
Diagnosis requires DNA testing, using cytogenetic analyses with the use of Giemsa staining.
Affected dogs are usually healthy and live a good quality of life.
- Larsen RE et al (1979) Breeding studies reveal segregation of a canine Robertsonian translocation along Mendelian proportions. Cytogenet Cell Genet 24(2):95-101
- Mayr B et al (1986) A new type of Robertsonian translocation in the domestic dog. J Hered 77(2):127
- Nolte M et al (1993) Different cytogenetic findings in two clinically similar leukaemic dogs. J Comp Pathol 108(4):337-342
- Switonski M et al (2011) Robertsonian translocation in a sex reversal dog (XX, SRY negative) may indicate that the causative mutation for this intersexuality syndrome resides on canine chromosome 23 (CFA23). Sex Dev 5(3):141-146
- Switonski M et al (2003) Robertsonian translocation (8;14) in an infertile bitch (Canis familiaris). J Appl Genet 44(4):525-527
- Stone DM et al (1991) A novel Robertsonian translocation in a family of Walker hounds. Genome 34(4):677-680
- Kolgeci S et al (2012) Recurrent abortions and down syndrome resulting from Robertsonian translocation 21q; 21q. Med Arh 66(5):350-352