The genotype and phenotype analysis in 3 cases with the rare genotype of HBB:c.316-146T > G

Abstract

Objectives To explore the genotypic and phenotypic characteristics of HBB: c.316-146T > G carriers in China.Methods The blood routine parameters and hemoglobin electrophoresis data of carriers were analyzed using PCR combined with reverse dot blot (RDB), gap-PCR, and DNA sequencing.Results The blood routine parameters of all these three cases were MCV G, the other one was heterozygous mutation of HBB:c.316-146T > G combined with –SEA deletion.Conclusion The hematological phenotype of HBB:c.316-146T > G mutation carriers is similar to that of common β+ heterozygous mutations, presenting with hypochromic, microcytic red cell indices. If the hematological phenotype does not match the results of genetic testing, further detection techniques such as Sanger sequencing, MLPA, next-generation sequencing (NGS), etc. are required to avoid missing rare or novel mutation types.

Keywords

• Β-thalassemia
• HBB:c.316-146T > G
• IVS-II-705(T > G)
• rare mutation
• clinical feature