Questions submitted during the Underlying Disease Screening in Dogs with IMHA webinar related to genetics and IMHA:
Is there a breed prevalence and risk for IMHA?
What evidence is there for an inherited genetic component for this disease? I have had a bitch that survived IMHA and a bitch she produced that did not survive.
Is it conceivable that a screening test could be developed in the future for breeding stock?
There are definite breed predispositons and several breeds are over represented. For example, Cocker spaniels Old English sheepdogs and Collies are commonly cited as being over represented, but IMHA is reported to be more common in several breeds in various studies. There are studies that have investigated and are investigating what genetic factors (such as DLA and CTLA genetics ) in populations overall and in particular breeds. For example see Friedenberg JG et al Evaluation of a DLA-79 allele associated with multiple immune-mediated diseases in dogs. Immunogenetics 2016 68(3) 205-217;Trelfall AJ et al. Analysis of DLA-DQB1 and polymorphisms in CTLA4 in Cocker spaniels affected with immune-mediated haemolytic anaemia. Canine Gen Epi 2015 9:2:8; Kennedy CJ et al. Association of a common dog leucocyte antigen class II haplotype with canine primary immune-mediated haemolytic anaemia. Tissue Antigens 2006 68(6) 502-8.
It is conceivable that a genetic test will be available in the future that will tell us who is at risk, especially with advances in genome wide sequencing, targeted gene sequencing and metabolomics. Controlled studies within breeds, requiring cooperation among breed owners will help pave the way to understanding the genetics of this disease in dogs and other species including people :).
