Genetic dissection of clinical heterogeneity in Hemoglobin H patients by targeted long-read sequencing

Yuhua Ye; Chao Niu; Aiping Mao; Li Chen; Lang Qin; Weijie Chen; Zhentian Liu; Tiantian Xie; Yong Long; Xuan Shang; Yushan Huang; Qianqian Zhang; Libao Chen; Hualei Luo; Yihong Li; Yulin Lu; Yumeng Liu; Liuhua Liao; Junqin Cai; Riyang Liu; Xinhua Zhang; Lihong Zeng; Yaoyun Li; Jianhong Chen; Zeyan Zhong; Jianpei Fang; Xinyu Li; Xingkun Yang; Bin Lin; Kui Li; Xiaoyun Hua; Binbin Huang; Honggui Qin; Yueyan Huang; Zhijing Huang; Jinquan Lao; Xiang Qu; Juanjuan Chen; Xiaoqin Feng; Qiujun Liu; Wanying Lin; Xiaoman Zhou; Yidan Liang; Xingjiang Long; Jiaofeng Qin; Lixiang Yan; Weijian Zhu; Lian Yu; Chengwu Fan; Deguo Tang; Tianyu Zhong; Jufang Tan; Zhilin Ren; Yang Gao; Xiangmin Xu

doi:10.1016/j.jgg.2026.04.011

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Genetic dissection of clinical heterogeneity in Hemoglobin H patients by targeted long-read sequencing

doi: 10.1016/j.jgg.2026.04.011

Funds:

Mufang Huang, Ying He, Panyan Zhou, Yanrong Hu, Dan Liu (Zhuhai People’s Hospital)

Xuan Shang, Xiaofeng Wei, Fu Xiong, Cunyou Zhao, Liang Li, Wanjun Zhou, Fei He, Zhen Zhao, Yuan Huang, Tongtong Chen, Mengyang Song, Congwen Shao, Shaomin Zou, Xingmin Wang, Jialong Li, Hailiang Liu, Peng Lin, Wei Zhang, Haoyang Huang, Tingfeng Zheng, Zongrui Shen, Dina Zhu, Yida Jiang (Southern Medical University)

Ken Huang, Huatuo Huang, Yuke Chen, Chengcai Chen, Jie Lu (Affiliated Hospital of Youjiang Medical University for Nationalities)

Zhirong Lu, Musheng Huang, Liping Huang (Sixth People's Hospital of Nanning)

Zhenzhong Tao, Neng Cheng, Yongzhang Wu, Shaobin Chen, Shuang Gao, Songbai Zheng, Fei Yuan, Xiaoye Tang, Ziping Zhong, Fuxia Li, Jia Li, Zhiling Ling (Guangzhou Huayinkang Healthcare Group Co., Ltd.)

Xinping Yang, Zhi Liu, Zilong He, Bingquan Lin, Wanxia Tan, Jing Du, Jianhui Yue, Jing Bai, Anhong Huang, Xingyuan Hu (Nanfang Hospital)

Zhenyuan Xia, Shaoke Chen (The Second Affiliated Hospital of Guangxi Medical University)

Qi Wang, Ning Qiu, Liuyuan Wei, Xiangzi Xie, Jing Chen, Likui Wu, Libo Qin, Xiaoli Xu (Liuzhou Worker's Hospital)

Chunchun Yuan, Yongjun Wang (Shanghai University of Traditional Chinese Medicine)

Zhixiang Liu, Ling Zeng (Heyuan Maternal and Child Health Care Hospital)

Caiyun Li (Chenzhou First People's Hospital)

Limin Li, Yuchen Zhu, Lixue Cheng (Liuzhou Worker's Hospital)

Uet Yu, Changgang Li (Shenzhen Children's Hospital), Zhenzhou Li (Second People's Hospital of Shenzhen) for their direct and indirect help in this study.

This study is supported by National Natural Science Foundation of China (82471895 to X.X.

Tao Huang, Bin Xu (Maternal and Child Health Hospital of Yongzhou City)

Xiang Guo (Sichuan Academy of Medical Sciences)

Peng Xu (Soochow University)

Medical Scientific Research Foundation of Guangdong Province, China (A2022278 to Y.Y.). We thank all the participants in this research and the Thalassemia Associations (Liuzhou, Huizhou, Shenzhen, Fujian, Guangzhou) for the assistance in the recruitment of subjects. We also thank Zilin Li (Northeast Normal University)

81900185 to Y.Y.

Shengwen Huang (Guizhou Provincial People's Hospital)

Pingping Li, Bo Zhang, Li Wang, Fang Yang (923(rd) Hospital of the People's Liberation Army)

Xiarong Li, Cuihua Hu, Ruixin Guo, Li Gao (GeneDock Co.Ltd.)

82370122 to X.S.)

Xiuxia Chen, Xianjin Wu, Xinxia Li (Huizhou Central People's Hospital)

Shuiling Shi, Yaowei Wen, Jinhua Fu, Lili Zhang (Longyan First Hospital)

Received Date: 2025-12-11
Accepted Date: 2026-04-17
Rev Recd Date: 2026-04-15

Available Online: 2026-04-25

Abstract

Abstract

Hemoglobin H (HbH) disease is a subtype of α-thalassemia typically caused by genetic defects in three out of four α-globin genes. To date, the genetic factors contributing to the highly heterogeneous clinical severity of HbH disease remain largely unknown. In this study, we perform targeted long-read sequencing (T-LRS) on a cohort of 591 HbH patients, aiming to profile the genomic variants and their haplotypes within the α/β-globin gene clusters and key erythroid genes. Phenotypic analysis confirms that non-deletional HbH patients generally exhibit more severe clinical manifestations compared to deletional ones. Moreover, we identify the co-inheritance of β-thalassemia mutations to be a mitigating factor for HbH patients, as reflected by higher hemoglobin levels and lower serum ferritin, suggesting the less imbalanced synthesis of α/β-globin among these patients. Furthermore, through haplotype phasing using long-sequencing reads, we find a haplotype of HS40 associated with milder clinical symptoms of HbH patients, validated by reporter gene assay, and that functional mutations in erythroid transcription factors BCL11A and MYB-HBS1L exert significant effects on β-thalassemia but not on HbH patients. This study presents the largest T-LRS study for α-thalassemia patients, which may provide insight into precise clinical diagnosis and phenotyping of HbH diseases.
- Thalassemia,
- Hemoglobin H,
- Targeted long read sequencing,
- Population study,
- Clinical heterogeneity

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