Novel mutations in RAG1/2 and ADA genes in Israeli patients presenting with T-B-SCID or Omenn syndrome.

[omenn syndrome]

The relative frequency of the different forms of SCID may vary in different countries . The most frequent form in Israel is the autosomal-recessive T -B- SCID or Omenn syndrome while X-linked SCID is rare . We report our immunological and genetic analyses in multicentre study of patients presenting with either T -B- SCID or Omenn syndrome . Among 16 patients , we identified 7 novel mutations in 6 patients . In the RAG 1 gene we detected two novel mutations : L 454 Q and 469 fs-4 bpdel . In the RAG 2 gene : 3 novel mutations : D 65 Y , G 157 V , and E 480 X . One T -B- SCID patient was found to be a compound heterozygote for new mutations in the ADA gene : W 264 X and R 235 W . Prenatal diagnosis was performed in 8 families while others refused due to religious reasons . Identification of the new mutations expands our knowledge regarding the unique features of SCID phenotype in Israel and may help the families seeking for genetic counseling .