Mutations in Thalassemia Carrier Couples: The Importance of Prenatal Diagnostic Tests.

BACKGROUND

Thalassemia carrier couples play an important role in increasing thalassemia patients. The study of thalassemia genotypes in carrier couples is also effective in improving genetic counseling for them. The aim of this study was to investigate the prevalence of thalassemia mutations and genotypes in couples.

METHODS

This cross-sectional study was performed on 241 couples who were suspected of thalassemia from April 2018 to March 2020 in Lorestan province. Statistical analysis of data was performed using SPSS software 16.0 (SPSS Inc., Chicago, IL, USA). Online tools such as www.ithanet.eu/db/ithagenes and http://globin.bx.psu.edu/ hbvar/menu.html were also used to match patients' mutations with known cases.

RESULTS

IVSII-1 (G>A), CD36-37 (-T), IVSI-110 (G>A), --Med, and α3.7 were the most common mutations in the beta and alpha genes, respectively. IVSII-1 (G>A) β0/β (26.1%), CD36-37 (-T) β0/β (21.1%), and IVSI-110 (G>A) β0/β (10.3%) genotypes were the most common in women. The frequency of these genotypes in men were 24.8%, 28.6%, and 12.8%, respectively. Among alpha thalassemia carriers, the α3.7α/α α genotype had the highest frequency among women (3.7%) and men (5.3%). Alpha and beta-thalassemia were 15 and 13 times higher in related women and 18 and 9 times higher in related men than non-related ones, respectively. This difference was statistically significant (p < 0.001). In addition, 12.8% of fetuses were thalassemia major, 31.9% beta thalassemia minor, and 10.3% normal.

CONCLUSIONS

Thalassemia screening in related couples plays an important role in reducing thalassemia major infants.