Veterinary/zoology session

Severe combined immunodeficiency disease (SCID) is an inherited autosomal, recessive hereditary disease carried by pure Arabian horses and their crossbreds. The foals with SCID have a deficiency both in the numbers and function of limphocytes, which leads to a lack activity of humoral and cellular immunity. The affected homozygous foals seem to be healthy at birth, but frequently die before the age of 5 months due to pneumonia or other opportunistic infection, because they are unable to produce immunglobulins after the excent of maternal immunity.

The genetic defect responsible for SCID is a 5-basepair deletion in the gene encoding the DNA-protein kinase catalytic subunit, the DNA- PKCS, whereby this frameshift-change destroy the function of the protein.

The SCID tests are based on length polymorphism (caused by 5 bp deletion) or allele specific oligonucleotide probes.

In our study the specifity and efficiency of different diagnostic methods were investigated, and first time was screened a Hungarian Arabian horse population.

Our results were shown that the length polymorphism detection method is the most usable as routine test.

According to the results of our tests, it is necessary to continue the molecular genetic screening of SCID in Hungarian Arabian populations.