title: Secondary mutation (c.94_95delAG) in a -α3.7 allele associated with Hb H disease in two unrelated African American individuals homozygous for the -α(3.7) deletion (-α3.7/-α3.7T).
abstract: Hb H disease is rarely seen in individuals of African descent although α-thalassemia (α-thal) is common in this population. Usually α-thal is due either to heterozygosity or homozygosity for the -α(3.7) deletion in this population. We report Hb H disease that is caused by a frameshift mutation on one -α(3.7) allele in two unrelated individuals homozygous for the -α(3.7) deletion. These two cases highlight the importance of further investigation by direct sequencing of the -α(3.7) allele when the thalassemic phenotype does not correlate with the genotype obtained by initial molecular testing.
authors.affiliation: Georgetown University, Washington, District of Columbia, USA.
authors.forename: Po
authors.initials: P
authors.lastname: Zhao
authors.forename: Arlene M
authors.initials: AM
authors.lastname: Buller-Burckle
authors.forename: Mei
authors.initials: M
authors.lastname: Peng
authors.forename: Alison
authors.initials: A
authors.lastname: Anderson
authors.forename: Z Jenny
authors.initials: ZJ
authors.lastname: Han
authors.forename: Monica V E
authors.initials: MV
authors.lastname: Gallivan
mesh_terms: D000293:Adolescent; D000328:Adult; D001741:Black or African American; D001483:Base Sequence; D004252:DNA Mutational Analysis; D005260:Female; D016368:Frameshift Mutation; D006447:Hemoglobin H / Q000235:genetics*; D006720:Homozygote; D006801:Humans; D008297:Male; D017384:Sequence Deletion; D055542:alpha-Globins / Q000235:genetics; D017085:alpha-Thalassemia / Q000235:genetics*
chemical_list: D055542:alpha-Globins; D006447:Hemoglobin H