Screening for mutations causing X-linked severe combined immunodeficiency in the IL-2R? chain gene by single-strand conformation polymorphism analysis

Abstract
Mutations in the common gamma chain (γc or IL2RG) of the interleukin-2, −4, −7, −9 and −15 receptors have been found to cause X-linked severe combined immunodeficiency (SCIDX1). We report here on the mutations identified in a further ten families. Two of the mutations identified have occurred twice in unrelated families, indicating two possible mutational hotspots. Seven of the mutations, which were identified by single-strand conformational polymorphism (SSCP) analysis, are point mutations, and the eighth is a small deletion. We also report on the first use of assays based on these mutations within IL2RG for unambiguous carrier determination. The consequences for the γc proteins produced as a result of these mutations are discussed.