First Report of Filipino β⁰-Thalassemia/β-Thalassemia in a Chinese Family

Abstract

A pregnant woman living in Fujian Province, southeastern China, presented due to a risk of having a baby with β-thalassemia major, during her second pregnancy, since she and her husband were suspected as β-thalassemia carriers and their affected daughter was a transfusion-dependent patient. Using the common α-thalassemia and β-thalassemia genotypes test, the pregnant woman was diagnosed as a β-thalassemia carrier with β^{IVS−2 − 654 (C→T)}/β^N genotype and her daughter had a homozygosity for IVS − 2 − 654 (C→T) mutation, however, no abnormalities were detected in her husband. SMRT identified a Filipino β⁰-deletion in her husband, and MLPA also revealed an unknown deletion in the HBB gene. Electrophoresis showed approximately 350 bp of the PCR product, and the β-Filipino genotype presented novel fracture fragments ranging from 5,112,884 to 5,231,358 bp, and lacked a 118,475 bp fragment relative to the wild-type sequence. The daughter was therefore diagnosed with the β^{IVS−2 − 654 (C→T)}/β^Filipino genotype. Prenatal diagnosis with umbilical cord blood at 27th week of gestation showed heteroztgosity for IVS − 2 − 654 (C→T) mutation in the fetus and continued pregnancy was recommended. In conclusion, we identified the Filipino β⁰-deletion in a Chinese family, from Fujian area, for the first time, during prenatal screening.

Keywords:

• β-thalassemia
• Filipino β⁰-deletion
• MLPA
• SMRT
• prenatal diagnosis

Acknowledgments

The authors would like to thank Ms Yu Zheng from Yaneng BioSciences (Shenzhen) Co.Ltd for the rare genetic assays of β-thalassemia.

Authors’ contributions

Na Lin, Liangpu Xu and Hailong Huang designed the study, Meihuan Chen and Aixiang Lv performed experimental studies, Meihuan Chen drafted the manuscript. Siwen Zhang, Junhao Zheng and Jianlong Zhuang collected the literature, Min Zhang, Lingji Chen and Qianqian He collected the data and prepared the manuscript. All authors approved the final manuscript.

Ethical approval

This study was proved by the Ethics Review Committee of Fujian Maternity and Child Health Hospital (2017–031).

Informed consent

Signed informed consent was obtained from all participants or their parents before starting study.

Disclosure statement

The authors confirm that they have no competing interests.

Availability of data and materials

The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Additional information

Funding

This work was funded by the National Natural Science Foundation of China (no. 81970170), Joint Funds for the innovation of science and Technology, Fujian province (no. 2021Y9173, no. 2021Y9174), Major Scientific Research Program for Young and Middle-aged Health Professionals of Fujian Province, China (no. 2023ZQNZD009) and Fujian provincial health technology project (no. 2019-CXB-20).