Variable genotype-phenotype correlations in patients with a rare nondeletional α-thalassemia; Hb Pak Num Po (HBA1: C.396-397insT)

Abstract

Transfusion-dependent Hb H disease is rarely reported. In the majority of patients, it is caused mainly by α-thalassemia from deletions of 2 linked α-globin genes and nondeletional mutations. Previously, we had described 2 unrelated Thai patients with this condition because of compound heterozygosity of SEA-type deletion (- -SEA/) and a novel nucleotide mutation: a thymine insertion at codon 131 of the α1 gene, namely, Hb Pak Num Po (Hb PNP, ααPNP). We herein describe the identification of 4 additional patients with Hb PNP with a broader genotype/phenotype spectrum and provide an overview of clinical management approaches including stem-cell transplantation. © 2014 by Lippincott Williams & Wilkins.