The Hb H Disease Genotypes in Southern China

Abstract

We report the genetic data of 435 patients with Hb H (β4) disease who presented at our center between 2005 and 2012. Our results showed that all patients had the Southeast Asian deletion (- -(SEA)) on one allele. The -α(3.7) (rightward) deletion was the most common on the other allele, followed by the -α(4.2) (leftward) deletion, Hb Constant Spring (Hb CS, α142, Term → Gln; HBA2: c.427T > C) and Hb Quong Sze [Hb QS, α125(H8)Leu → Pro; HBA2: c.377T > C] mutations. Two rare point mutations, α31(B12)Arg → Lys; HBA2: c.95G > A and Hb Zurich Albisrieden [α59(E8)Gly → Arg; HBA1: c.178G > C], were also identified. Four patients had a concomitant β-thalassemia (β-thal) heterozygosity. Our results reflect the genetic heterogeneity of Hb H disease and the interaction between Hb H disease and β-thal trait in Southern China.

Severe fetal anemia and hydrops fetalis associated with compound heterozygosity for Hb Zurich-Albisrieden (HBA2:c.178G>C) and Hb Quong Sze (HBA2:c.377T>C)

“…Two children with transfusion-dependent Hb H disease were subsequently reported, both of whom had Hb ZA compounded with the Southeast Asian (-- SEA ) deletion. 10,11 A Brazilian child with thalassemia major phenotype homozygous for the Hb ZA mutation, who was dependent on blood transfusions and was being prepared for bone marrow transplantation, has also been reported. 8 A case of Hb H hydrops fetalis associated with compound heterozygosity for Hb ZA and the -- SEA deletion, with Hb 55 g/L, was reported at 25 weeks of gestation.…”

Research of artificial intelligence in imperfect information card games

“…It was shown by You et al, 2019 that this algorithm only had a 30% winning rate against humans when the computer played as peasants [17]. DeltaDou achieved expert-level play by incorporating Fictitious Play MCTS and a policy-based inference algorithm into a framework similar to AlphaZero [18]. However, the methods used by DeltaDou are computationally costly and rely on human abstractions.…”

HbH disease due to compound heterozygosity for hemoglobins Zürich‐Albisrieden and Sallanches

“…Hb Zürich‐Albisrieden was described in 2004 . The only six prior reports are from Switzerland, China, and Brazil . This hyperunstable Hb causes a thalassemia major phenotype in homozygotes (α ZA α/α ZA α), HbH disease in compound heterozygotes (α ZA α/α T α or α ZA α/‐α), and hypochromic microcytosis with mild erythrocytosis in heterozygotes (α ZA α/αα) …”

“…6 The only six prior reports are from Switzerland, China, and Brazil. 1,[6][7][8][9] This hyperunstable Hb causes a thalassemia major phenotype in homozygotes ( ZA / ZA ), HbH disease in compound heterozygotes ( ZA / T or ZA /-), and hypochromic microcytosis with mild erythrocytosis in heterozygotes ( ZA / ). 1,[6][7][8][9] Our patient, in addition to expanding the list of genotypes resulting in HbH disease and being the first reported instance of this rare combination worldwide, also highlights other diagnostically relevant points.…”

“…The inappropriate immunosuppressive therapy due to the single 2+ DCT in a recently transfused patient who may have developed clinically insignificant alloantibodies also highlights the importance of evaluating weak or low‐grade positive DCT results from the perspective of the complete clinical scenario . Unlike unstable β‐globin chain variants, unstable α‐chain variants tend to be symptomatic only in homozygous or compound heterozygous states . Molecular techniques remain the mainstay for definitive typing of HbH disease suspected on HPLC.…”