Mild beta-thalassemia intermedia caused by compound heterozygosity for (G)gamma((A)gammadeltabeta)(o)/beta-thalassemia and molecular characterization of the defect in four Chinese families.
Molecular characterization of the compound heterozygous condition - (G)gamma((A)gammadeltabeta)(o)/beta-thalassemia - in four families showing mild beta-thalassemia intermedia was carried out using DNA amplification techniques. Using the Amplification Refractory Mutation System (ARMS) to confirm the beta-mutations and DNA amplification to detect the 100-kb Chinese-specific (G)gamma((A)gammadeltabeta)(o)-deletion, ()two families were confirmed to possess (G)gamma((A)gammadeltabeta)(o)/beta-thalassemia with the IVSII No. 654 beta(+)-allele. In the third family, the (G)gamma((A)gammadeltabeta)(o)-deletion was confirmed in the father and the mother was a beta-thalassemia carrier with the cd 41-42 beta(o)-allele. Their affected child with (G)gamma((A)gammadeltabeta)(o)/beta-thalassemia was found to be transfusion dependent. The same (G)gamma((A)gammadeltabeta)(o)-deletion and beta-thalassemia (cd 41-42) was also confirmed in a fourth family. In addition, the mother was also diagnosed with Hb H disease (genotype -alpha(3.7)/-(SEA)). Both the children were found to possess (G)gamma((A)gammadeltabeta)(o)/beta-thalassemia but they were not transfusion dependent and this could be due to co-inheritance of alpha-thalassemia-2 (genotype-alpha(3.7)/alphaalpha) in the children together with their compound heterozygous condition.
Tan Jin Ai
Mary Anne
MA
Department of Allied Health Sciences, Faculty of Medicine, University of Malaya, Lembah Pantai, Kuala Lumpur, Malaysia. jamatan@hotmail.com
Yap
Sook Fan
SF
Tan
Kim Lian
KL
Wong
Yean Ching
YC
Wee
Yong Chui
YC
Kok
Juan Loong
JL
D000328:Adult; D000483:Alleles; D001797:Blood Protein Electrophoresis; D001803:Blood Transfusion; D002648:Child; D002681:China / Q000208:ethnology; D004247:DNA / Q000235:genetics; D004252:DNA Mutational Analysis; D005260:Female; D005319:Fetal Hemoglobin / Q000032:analysis; D005784:Gene Amplification; D005838:Genotype; D005914:Globins / Q000235:genetics*; D006443:Hemoglobin A2 / Q000032:analysis; D006579:Heterozygote; D006801:Humans; D008296:Malaysia; D008297:Male; D010375:Pedigree; D010641:Phenotype; D012150:Polymorphism, Restriction Fragment Length; D017384:Sequence Deletion; D017085:alpha-Thalassemia / Q000235:genetics*; D017086:beta-Thalassemia / Q000235:genetics* / Q000628:therapy
D005914:Globins; D004247:DNA; D006443:Hemoglobin A2; D005319:Fetal Hemoglobin