Thalassemia intermedia due to co-inheritance of beta0/beta(+)-thalassemia and (- -SEA) alpha-thalassemia/Hb Westmead [alpha122(H5)His > Gln (alpha2)] in a Chinese family.
Two brothers from a Chinese family with beta-thalassemia intermedia who harbor both alpha- and beta-globin gene defects are described. They are both compound heterozygous for codons 41/42 (-CTTT) beta0-thalassemia and nt - 28 (A > G) beta(+)-thalassemia mutations together with concurrent (- -SEA) alpha-thalassemia (SEA) deletion. One sibling also harbors Hb Westmead, giving an unusual genotype of beta0/beta(+)-thalassemia and (- -SEA) alpha-thalassemia/Hb Westmead. With respect to the age at presentation and transfusion requirement, this subject shows a milder clinical phenotype than his brother, most probably explainable by the presence of Hb Westmead in addition to the SEA deletion, which causes a further amelioration of the alpha-chain excess and hence a less severe disease. For areas with high prevalence of both alpha- and beta-thalassemia mutations, their interactions should always be considered in genotype phenotype correlation. Moreover, routine laboratory diagnostic strategy for non-deletional alpha-globin gene mutations in the Chinese may need to include Hb Westmead, as it is a common alpha-globin gene mutation in our population apart from Hb Constant Spring and Hb Quong Sze.
Wong
Wai-Shan
WS
Division of Hematology, Department of Pathology, The University of Hong Kong, Queen Mary Hospital, Hong Kong, PR China.
Chan
Amy Y Y
AY
Yip
Sze-Fai
SF
Ma
Edmond Shiu-Kwan
ES
D000328:Adult; D044466:Asian People; D002681:China; D003062:Codon / Q000235:genetics; D004252:DNA Mutational Analysis; D005190:Family; D005838:Genotype; D005914:Globins / Q000235:genetics* / Q000378:metabolism; D005973:Glutamine / Q000235:genetics; D006455:Hemoglobins, Abnormal / Q000235:genetics* / Q000378:metabolism; D006639:Histidine / Q000235:genetics; D006801:Humans; D002479:Inclusion Bodies / Q000378:metabolism; D008297:Male; D010641:Phenotype; D017384:Sequence Deletion / Q000235:genetics; D017085:alpha-Thalassemia / Q000235:genetics*; D017086:beta-Thalassemia / Q000235:genetics* / Q000378:metabolism
D003062:Codon; D006455:Hemoglobins, Abnormal; D005973:Glutamine; C045396:hemoglobin Quong Sze; D006639:Histidine; C056329:Hemoglobin Westmead; D005914:Globins; C035541:Hemoglobin Constant Spring