Clinical features and gene mutation spectrum in children with sideroblastic anemia
AN Wen-Bin1,2, LIU Chao1,2, WAN Yang1,2, GUO Ye1, WANG Shu-Chun1, ZHANG Ying-Chi2, ZHU Xiao-Fan1,2
Pediatric Blood Diseases Centre, Institute of Hematology and Blood Diseases Hospital, Chinese Academy of Medical Sciences & Peking Union Medical College, Tianjin 300020, China
Abstract：Objective To study the clinical features and gene mutation spectrum of children with sideroblastic anemia (SA) and the clinical value of targeted next-generation sequencing in the molecular diagnosis of children with SA. Methods Clinical data were collected from 36 children with SA. Targeted next-generation sequencing was used to detect mutations in SA-related pathogenic genes and genes associated with heme synthesis and mitochondrial iron metabolism. The association between genotype and clinical phenotype was analyzed. Results Of the 36 patients, 32 had congenital sideroblastic anemia (CSA) and 4 had myelodysplastic syndrome with ring sideroblasts (MDS-RS). Mutations in CSA-related genes were detected in 19 children (19/36, 53%), among whom 9 (47%) had ALAS2 mutation, 4 (21%) had SLC25A38 mutation, and 6 (32%) had mitochondrial fragment deletion. No pathogenic gene mutation was detected in 4 children with MDS-RS. Among the 19 mutations, 89% (17/19) were known mutations and 11% (2/19) were novel mutations. The novel mutation of the ALAS2 gene c.1153A >T(p.I385F) was rated as "possibly pathogenic" and the novel mutation of the SLC25A38 gene c.175C > T(p.Q59X) was rated as "pathogenic". Conclusions ALAS2 and SLC25A38 gene mutations are commonly seen in children with CSA, but mitochondrial gene fragment deletion also accounts for a relatively high proportion. For children with hypoplastic anemia occurring in infancy, mitochondrial disease should be considered.
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