Background: Foetal haemoglobin (Hb F) level modifies clinical severity of HBB disorders. Intergenic variants of HBS1L-MYB on chromosome 6q23 have recently been shown to be a major quantitative trait locus (QTL) influencing Hb F levels in normal Caucasian adults.
Methods: A unique and well-characterised cohort of 238 Chinese subjects with £] thalassaemia trait was used to conduct a single nucleotide polymorphism (SNP) association study for Hb F level.
Results: Within this locus, 29 trait-associated SNPs in a non-coding 56 kb segment were identified. They were divided into 5 linkage disequilibrium (LD) blocks in Chinese.
Conclusions: The data independently validate for the first time the significance of the HBS1L-MYB intergenic region in regulating Hb F expression in a separate ethnic group that has a high prevalence of £] thalassaemia. Functional studies to unravel the biological significance of this region in regulating Hb F production is clearly indicated, which may lead to new strategies to modify the disease course of severe HBB disorders.