Identification of two novel β°-thalassemia mutations in a filipino family: Frameshift codon 67 (− TG) and a β-globin gene deletion

The frequency of β-thalassemia alleles among Filipinos is estimated to be 0.02, although little is known about the actual mutations represented in this population. Here, we describe a Filipino family in which a child has severe β-thalassemia major. Molecular studies of the family revealed that the proband is a compound heterozygote for two previously unreported β°-thalassemia alleles: a frameshift mutation ( − TG) at codon 67 and a deletion of the entire β-globin gene. The 5′ endpoint of this novel deletion is located ∼3.9 kb to ∼4.3 kb upstream of β-globin gene, and the deletion extends 3′ beyond the β-globin gene for an undetermined distance. The occurrence of two novel β-thalassemia alleles in a single family suggests that the Filipino population may have a unique spectrum of β-thalassemia alleles. © 1993 Wiley-Liss, Inc.