[Gene Diagnosis and Phenotypic Analysis of β-Thalassemia Caused from a Rare Synonymous Mutation CD29 (C>T)].

Objective: To investigate the gene diagnosis and phenotypes analysis for a couple with β-thalassemia suspected from of blood routine test and hemoglobin electrophoresis, as well as the prenatal gene diagnosis of the fetus.

Methods: The gene mutation of β-globin in the samples of peripheral blood of pregnant woman and her husband, as well as amniotic fluid of pregnant woman were analyzied and identified by using PCR-RDB and Sanger sequencing.

Results: The detection showed that the heterozygote mutation of IVS-Ⅱ-654 (C>T), which is common mutation of β-globin gene, existed in pregnant woman, while her husband carried a rare mutation CD29 (c.90 C>T) of β-globin gene. The prenatal diagnosis indicated that the fetus inherited with mutation from the parents, fetus genotype was β/β.

Conclusion: The CD29(C>T) mutation of β-globin gene has been identified in Chinese population first. Although this mutation type is symonymous mutation, but its carrier displays phenotype of β-thalaessmia. Therefore, the attention to this mutation should be paid considering the genetic risk. It contributes to genetic counseling and prenatal gene diagnosis.