[The characteristic of hereditary spherocytosis related gene mutation in 37 Chinese hereditary spherocytisis patients]

Clinical and genetic characteristics of Chinese pediatric and adult patients with hereditary spherocytosis

OBJECTIVE

This study aimed to investigate the clinical features, pathogenic gene variants, and potential genotype-phenotype correlations in Chinese patients with hereditary spherocytosis (HS).

METHODS

Retrospective analysis of clinical data and molecular genetic characteristics was conducted on patients diagnosed with HS at Jiangxi Provincial Children's Hospital, the Second Affiliated Hospital of Nanchang University, Pingxiang People's Hospital and The Third People's Hospital of Jingdezhen between November 2017 and June 2023. Statistical analyses were performed to compare and analyze the red blood cell (RBC), hemoglobin (HB), mean corpuscular volume (MCV), mean corpuscular hemoglobin (MCH), and mean corpuscular hemoglobin concentration (MCHC) data between and within groups based on different mutations and age groups (< 14 and ≥ 14 years).

RESULTS

A total of 34 HS patients were included in this study, comprising 22 children (64.70%) and 12 adults (35.30%). The probands who underwent genetic testing were derived from 34 unrelated families. Thirty-two variants were tested and 9 of them are novel. Eighteen cases had ANK1 variants, 15 had SPTB variants, and 1 had SLC4A1 variant. 25 patients performed core family members underwent genetic testing, 17 (68.0%, 17/25) were de novo, 5 (20.0%, 5/25) were maternally inherited, and 3 (12.0%, 3/25) were paternally inherited. ANK1-HS patients exhibited more severe anemia compared to cases with SPTB-HS, showing lower levels of RBC and HB (P < 0.05). Anemia was more severe in patients diagnosed in childhood than in those diagnosed in adulthood. Within the ANK1-HS group, MCH levels in adult patients was significantly higher than those in children (P < 0.05), while there were no significant differences in RBC, HB, MCV, and MCHC levels between two groups. Adult patients with SPTB-HS had significantly higher levels of RBC, HB, and MCH than pediatric patients (P < 0.05), while MCV and MCHC levels showed no significant statistical differences.

CONCLUSION

This study conducted a comparative analysis of phenotypic characteristics and molecular genetics in adult and pediatric patients diagnosed with HS, confirming that pediatric ANK1-HS patients exhibit a more severe anemic phenotype compared to SPTB-HS patients, while the severity of HS in adults does not significantly differ between different causative genes.

The Correlation Between Clinical Phenotype and Genotype of Hereditary Spherocytosis

Objective: Hereditary spherocytosis (HS) is a common hereditary hemolytic disease. This study aimed to explore the correlation between the phenotype and mutant genotype of HS to improve the clinical understanding of HS. Methods: This study reported a case of spontaneous mutation of the ANK1 gene in HS, reviewed previous studies on the genotype-phenotype correlation of HS, statistically analyzed the main types of gene mutations in HS, and summarized the clinical data of patients. Results: This patient had clinical manifestations of anemia, splenomegaly, peripheral blood smear with increased spherocytosis, and bilirubin, confirmed as ANK1 gene mutant HS by gene detection. In addition, this study included 14 previous studies on genotype-phenotype correlation, collected data, and determined that the ANK1 and SPTB genes were the most common types of gene mutations in HS patients. The mutant HS of the ANK1 gene would lead to lower hemoglobin levels. Conclusion: The results of this study showed that ANK1 and SPTB were the most common types of gene mutations in HS patients. Compared with patients with the SPTB genotype HS, patients with ANK1 mutant HS had more severe extravascular hemolysis, and a higher proportion needed splenectomy in early childhood.

A large family of hereditary spherocytosis and a rare case of hereditary elliptocytosis with a novel SPTA1 mutation underdiagnosed in Taiwan: A case report and literature review

RATIONALE

Hereditary spherocytosis (HS) has a defect in the vertically connected proteins on the cell membrane of red blood cells (RBC). Hereditary elliptocytosis (HE) has a defect in proteins that connect the cell membrane horizontally. We reported two families of RBC membrane disorders in Taiwanese, one was HS and the other was HE.

PATIENT CONCERNS

Case 1. A 19-year-old male student with chronic jaundice and splenomegaly. His mother, maternal uncle, grandmother, and many members of older generations also had splenomegaly and underwent splenectomy. Case 2. A 40-year-old man has experienced pallor and jaundice since the age of 20 and was found to have splenomegaly, and gall bladder stones in the older age. His younger sister also had pallor and jaundice for a long time.

DIAGNOSES

In case 1, a peripheral blood smear showed 20% spherocytes. Eosin-5-maleimide labeled RBC by flow cytometry showed a result of 30.6 MCF (cutoff value: 45.5 MCF). He was diagnosed with HS. The gene analysis identified a heterozygous mutation with c.166A > G (p.Lys56Glu) in the SLC4A1 gene in this proband, his mother, and maternal uncle. In case 2, more than 40% of ellipsoid RBC present in the peripheral blood smear. He was diagnosed with HE. Genetic analysis of the SPTA1 gene identified a novel heterozygous exon2, c.86A > C, p.Gln29Prol mutation.

INTERVENTIONS

The two patients had compensated anemia, clinical follow-up instead of splenectomy was done.

OUTCOMES

The two patients had normal daily activities and lives.

LESSONS

We reported two Taiwanese families, one was hereditary spherocytosis affected by a heterozygous mutation with c.166A > G (p.Lys56Glu) in SLC4A1, and the other was hereditary elliptocytosis caused by a novel heterozygous SPTA1 gene mutation, c. 86A > C, p.Gln29Prol. These 2 seemingly common hereditary red blood cell membrane protein defects induced by hemolysis are usually underdiagnosed or misdiagnosed.

A novel variant of SLC4A1 for hereditary spherocytosis in a Chinese family: a case report and systematic review

BACKGROUND

The incidence of hereditary spherocytosis (HS) is approximately 1:2000 in the western population, while it is much lower in the Chinese population. It is difficult to make a definite diagnosis due to the variable genotypic features and the lack of well-documented evidence for HS patients. Gene sequence examination is helpful for clear diagnosis.

CASE PRESENTATION

We presented the case of a 29-year-old male HS patient with skin yellowness, anorexia, and cholecystolithiasis as the first manifestations. Laboratory examination of the patient and his parents showed a mild reduction in hemoglobin and mean corpuscular hemoglobin concentration, increased reticulocytes, and promotion of indirect bilirubin in the patient and his father. Furthermore, small globular red blood cells with increased osmotic fragility were observed. In particular, the eosin-5'-maleimide binding test provided the strong evidence that band 3 protein was deleted in the erythrocyte membrane. Next-generation sequencing (NGS) and Sanger sequencing further demonstrated a heterozygous nonsense variant (exon16, c.G1985A: p.W662X) in SLC4A1, inherited from his father. Thus, the patient was diagnosed with HS, and then was effectively treated. After splenectomy, the anemia was relieved without any obvious unpleasant side effects.

CONCLUSION

We report an extremely rare case of HS in China that presented with hereditary hemolytic anemia with band 3 deletion resulting from a novel variant of SLC4A1, and systematically review a large number of related literatures. This study, therefore, significantly contributes to the literature on HS.

The updated beta-spectrin mutations in patients with hereditary spherocytosis by targeted next-generation sequencing

Hereditary spherocytosis (HS) with hemolysis, splenomegaly, and jaundice as the main clinical symptoms varied in different population and SPTB mutated rate is common except for ANK1 in the Chinese population, whereas only a few studies have been reported. Here, 11 Chinese pediatric patients with newly SPTB mutations detected by targeted next generation sequencing technology were included and analyzed in our study. The characteristics of mutation separation were verified among family members by bidirectional Sanger sequencing. The detected 11 mutations were novel, all of which were heterozygotes, including five de novo mutations, five maternal mutations, and one paternal mutation. Meanwhile, the 11 different novel mutation sites distributed on and near the seven exons included four pathogenic sites and seven likely pathogenic sites. The detection of 11 novel mutation sites gene expanded the mutant spectrum of the SPTB gene, and provided corresponding clinical data, which laid a foundation for the subsequent studies on HS in Chinese population, especially in pediatric patients.

Clinical utility of targeted gene enrichment and sequencing technique in the diagnosis of adult hereditary spherocytosis

Background

The present study aimed to use the targeted capture and sequencing technique to diagnose adult hereditary spherocytosis (HS). These results were compared with clinical features and laboratory examinations to explore the diagnosis of HS.

Methods

Whole blood and clinical data from ten patients with HS were collected. Genomic DNA was extracted, and a library was prepared. Exomes of patients with ten HS-related genes encoding red cell membrane skeleton protein were captured and sequenced. Bioinformatics analyses were carried out throughout the 1000 Genomes Project, ExAC, dbSNP147, and 1000 Normal Han Population databases.

Results

Gene mutations were found in 9 out of 10 cases of HS. Our data validation showed 90% specificity. Three types of gene mutations were found, including 6 cases of SPTB, 3 cases of ANK1, and 2 cases of SLC4A1. There were 4 mutation forms, including nonsense mutation, missense mutation, shear mutation, and code shift mutation, all of which were new, heterozygous mutations. These variations were predicted to be pathogenic in four databases.

Conclusions

Our data demonstrate that targeted gene enrichment and sequencing methods were an efficient tool for determining genetic etiologies of red blood cell (RBC) membrane disorders and can facilitate accurate diagnosis and genetic counseling. They are also in good agreement with the clinical results.