Molecular characterization of alpha-thalassemia in the Mexican population.

BACKGROUND alpha-Thalassemia (alpha-Thal) has been poorly characterized at the molecular level in Mexico. METHODS 106 consecutive individuals identified in Laboratorios Clínicos de Puebla, with either hypochromia (MCH < 24 pg) and/or microcytosis (MCV < 75 fl in women or < 80 fl in man), without iron deficiency, with or without anemia were investigated in this study, along a 16 month-period. alpha and beta-Thal were looked for, the former were characterized at the molecular level. RESULTS Out of the 106 consecutive cases with hypochromia and/or microcytosis and normal levels of protoporphyrin zinc complex, 48 cases (45.3%) had thalassemia (37 cases of betaThal and 11 cases of alphaThal), whereas in 58 cases (54.7%) a definite diagnosis could not be established. Of the alpha-Thal cases, 8 were heterozygous and two were homozygous for the -alpha3.7 deletion, whereas one case was heterozygous for the alpha2Hph allele. CONCLUSIONS Only few of the alpha-Thal alleles tested were found, thus the alpha-thalassemic mutations, present in the studied population, seem to be rather heterogeneous.