The diagnosis and molecular analysis of a novel 27.2 kb deletion causing α0-thalassemia.

BACKGROUND:Thalassemia, one of the most prevalent monogenic diseases worldwide, is caused by an imbalance of α-like and non-α-like globin chain production. Copy number variations, which cause the most common genotype of α-thalassemia, can be detected by multiple diagnostic methods. CASE REPORT:The proband was a 31-year-old female who was diagnosed with microcytic hypochromic anemia by antenatal screening. Hematological analysis and molecular genotyping were conducted on the proband and the proband's family members. Gap-polymerase chain reaction, Sanger sequencing, multiplex ligation-dependent probe amplification, and next-generation sequencing were used to detect potentially pathogenic genes. Familial studies and genetic analyses revealed a novel deletion of 27.2 kb located in the α-globin gene cluster (NC_000016.9: g. 204538_231777delinsTAACA). CONCLUSIONS:We reported a novel α-thalassemia deletion and described the process of molecular diagnosis. The novel deletion extends the thalassemia mutation spectrum, which may be helpful in genetic counseling and clinical diagnosis in the future.