A case series of α-thalassemia intermedia due to compound heterozygosity for Hb Adana [HBA2: c179G>A (or HBA1); p.Gly60Asp] with other α-thalassemias in Malay families.
Hb Adana [HBA2: c179G>A (or HBA1); p.Gly60Asp] is a rare hemoglobin (Hb) variant due to a mutation at codon 59 of the α2- or α1-globin gene resulting in a glycine to aspartic acid substitution. Two siblings with a unique coinheritance of Hb Adana and Hb Constant Spring (Hb CS, α142, Term→Gln, TAA>CAA; HBA2: c.427 T>C) (α(codon 59)α/α(CS)α), were compared phenotypically with another two siblings carrying the Hb Adana mutation and a 3.7 kb deletion (α(codon 59)α/-α(3.7)). Although they all had α-thalassemia intermedia (α-TI), the former were clinically more severe than the latter. The first pair of siblings presented at a much younger age than the second pair and showed lower Hb levels and significant extramedullay hemopoiesis. Another case of a hydropic fetus as a result of Hb H/Hb Adana is also described. Their clinical phenotypes and hematological parameters are all presented for comparison.
Haematology Unit, Department of Pathology, Universiti Kebangsaan Malaysia Medical Centre , Kuala Lumpur , Malaysia .
Hafiza
H
Alauddin
Noor-Adilah
NA
Jaapar
Raja Z
RZ
Azma
Azlin
A
Ithnin
Noor-Farisah A
NF
Razak
C-Khai
CK
Loh
Hamidah
H
Alias
Zarina
Z
Abdul-Latiff
Ainoon
A
Othman
D000293:Adolescent; D000328:Adult; D000483:Alleles; D019943:Amino Acid Substitution; D002648:Child; D005260:Female; D006455:Hemoglobins, Abnormal / Q000235:genetics*; D006579:Heterozygote; D006801:Humans; D008296:Malaysia; D008297:Male; D010375:Pedigree; D011247:Pregnancy; D011256:Pregnancy Outcome; D035781:Siblings; D055815:Young Adult; D017085:alpha-Thalassemia / Q000097:blood / Q000175:diagnosis / Q000235:genetics*
D006455:Hemoglobins, Abnormal; C083925:hemoglobin Adana
Codon 59 mutation; Hb Adana; Hb Constant Spring (Hb CS); – –SEA; −α3.7