Two new polymorphisms in the human interferon gamma (IFN-γ) promoter

Two new single-nucleotide polymorphisms are described within the human interferon gamma (IFN-gamma) promoter in a Sudanese population. One is a G to T transition at position -183 from the transcription start. The other is a A to G transition at position -155. Allelic frequency analysis indicated frequencies of 0.927 (G) and 0.073 (T) at position -183 and 0.977 (A) and 0.023 (G) at position -155. These two polymorphisms have not been detected in the Centre d'Etude du Polymorphisme Humain (CEPH) reference population. The polymorphism -183(G --> T) may alter the AP-1 binding domain and the regulation of transcription. The polymorphism -155(A --> G) is located close to the nuclear factor-activated T-cell site (NFAT site) (-168 TAAAGGAAA-160) and may affect the stability of this region.