Severe hereditary immunodeficiency of the foal (FIS) caused by a variant in SLC5A3 (myo-inositol transporter). It presents with immunodeficiency, anaemia, growth retardation and early death. Autosomal recessive inheritance. The test is complementary to the clinical examination and the immunological profile.

Dales and Fell Pony. Frequencies: limited data.

- Small foals with poor growth
- Recurrent infections due to immunodeficiency
- Anaemia
- Death in the first months of life

The dossier records the SLC5A3 gene and the variant NC_009169.3:g.31894278C>T (NM_001247992.1:c.1352C>T; p.Pro451Leu). No author or year is stated.

- Genotype breeding animals
- Avoid carrier × carrier matings
- Do not use carriers in high-risk breeding programmes

Differential diagnosis with autosomal SCID (PRKDC) and other foal immunodeficiencies. Complementary: blood count, immunoglobulins and lymphocyte subsets.

1. OMIA:001578 Inmunodeficiencia (SLC5A3) del caballo