STAT3 variants in T-Cell Large Granular Lymphocytic Leukaemias and Chronic Lymphoproliferative Disorders of Natural Killer Cells

Variants in exons 20 and 21 of the STAT3 gene have been identified in both T-cell and NK cell diseases, approximately one-third of patients with these disorders harbour STAT3 gene variants (Jerez et al. (2012) Blood 120: (15) 3048-3057). Recurrent variant hot spots in exon 21 of the STAT3 gene have been identified in large granular lymphocytic leukaemia which include; p.(Tyr640Phe), p.(Asp661Val), p.(Asp661Tyr) and p.(Asn647IIe) (Koskela et al.  (2012) N ENGL J MED 366: (20) 1905-1913). The identification of STAT3 variants can therefore be used as a tool in the differential diagnosis of large granular lymphocytic leukaemia and lymphoproliferations involving T and NK cells.  However, all molecular data must be interpreted with other histological and clinical data.

STAT3 variants (exons 20 and 21 only) are identified by bi-directional Sanger sequencing which will detect variants present at a level of greater than 10%.

Laboratory contact:  Dr. Caroline Wickham 01392 408252 caroline.wickham@nhs.net Clinical contact: Dr. Paul Kerr 01392 402917 paul.kerr1@nhs.net