Literature review on genotype-phenotype correlation in patients with hereditary spherocytosis

Understanding the genetic architecture and phenotypic landscape of SPTB gene variants causing hereditary spherocytosis in an Indian cohort

Hereditary spherocytosis (HS) is a common form of haemolytic anaemia caused by defects or deficiencies in genes encoding erythrocyte membrane proteins, such as ANK1, SPTB, SLC4A1, EPB42, and SPTA1. Among these, ANK1 and SPTB mutations are the most frequent causes of HS worldwide. This study analysed 53 Indian HS patients, identifying 33 novel and 12 previously reported SPTB variants using targeted next-generation sequencing (t-NGS). The identified SPTB variants included frameshift (28%), missense (24%), nonsense (44%), and splicing (4%) types, with nonsense variants being the most common. These nonsense variants typically result in truncated proteins. The variants were widely distributed across the gene, with the highest density observed in the spectrin repeats and ankyrin-binding domain, while no variants were found in the tetramerization domain. All identified SPTB variants exhibited heterozygous inheritance, consistent with an autosomal dominant inheritance pattern of the gene causing HS. One patient, however, carried compound heterozygous variants, leading to severe anaemia, and five patients had de novo SPTB variants. This study expands the spectrum of SPTB variants, enhances the understanding of spectrin-related molecular defects, establishes genotype-phenotype correlations, and provides valuable insights for laboratories developing genetic tests for HS. The high number of identified variants highlights the importance of advanced technologies like NGS for accurate molecular diagnosis in HS disorder. This approach not only supports clinical diagnostics but also aids in family counseling for improved management of HS.

Clinical characteristics of hereditary spherocytosis with red blood cell membrane protein gene variants

The clinical manifestations of hereditary spherocytosis (HS) are often heterogeneous, spanning from asymptomatic to severe symptoms that may pose life-threatening risks. Genotype-phenotype correlations remain controversial in clinical research. This retrospective study evaluated the correlation between genetic variants and clinical characteristics in a cohort of 64 Chinese pediatric patients with HS. The predominant variants were found in the ANK1 (27 cases, 42%) and SPTB (26 cases, 41%) genes, while variants in the SPTA1 (6 cases, 9%) and SLAC4A1 genes (5 cases, 8%) were less common. No EPB42 variants were detected. A total of 71 variants were identified. Variation types included nonsense (21%), missense (27%), frameshift mutations (39%), splicing (8%), and large fragment deletions (4%). No statistical differences in hemoglobin levels, MCV, MCH, MCHC, or reticulocytes were observed across the various genetic variant groups. Bilirubin levels were remarkably elevated in patients with HS variants, and those with SPTB-HS had significantly higher bilirubin levels, including total bilirubin (p = 0.033) and indirect bilirubin (p = 0.018) compared to those with SPTA1-HS. Moreover, those with the ANK1 variants displayed reduced resistance to lysis at varying NaCl concentrations in comparison to those with the SPTA1 variants (p = 0.047). In short, patients with the ANK1 and SPTB variants had the most severe disease, while those with the SPTA1 variants had the mildest. Genetic testing is advised in patients without a family history or who are difficult to diagnose with routine laboratory tests, as this may also provide references for clinical treatment and genetic counseling.

Two Variants of the ANK1 Gene Associated with Hereditary Spherocytosis

Background Hereditary spherocytosis (HS) is an erythrocytic membranopathy that belongs to a group of rare genetic disorders. Mutations in five genes, including ANK1, cause clinical manifestations of the disease. Identified variations in individual families provide a better understanding of the molecular basis of the disease. Methods In this study, we used two sequencing methods, whole exome sequencing (WES) and Sanger sequencing, analyzing gDNA and cDNA as templates, to detect and verify the variants putatively responsible for the clinical symptoms observed in a Polish family diagnosed with HS. Results We detected two variants that occur in cis in the ANK1 gene, a known missense mutation (NP_000028.3:p.V463I) and a novel frameshift mutation (NP_000028.3: p.V1626fs*64) that appears to be crucial for the probands. As shown by transcriptome studies, the mutant allele is not present at a detectable level. Conclusions We conclude that the molecular basis of this case is related to an unstable transcript of the mutant allele and that the direct cause of the HS is a deficiency of erythrocyte ankyrin leading to a disruption of the AE1-erythrocyte ankyrin-spectrin complex in the erythrocyte membrane.

Genetic screening strategy for children with hereditary spherocytosis in Jiangxi Province of China

Objective

This study aims to provide a comprehensive summary of the clinical phenotypic characteristics of children with anemia of unknown etiology, particularly focusing on the early detection of hereditary spherocytosis (HS) and exploring genetic screening strategies for this condition in childhood.

Methods

The study included children with anemia whose underlying cause could not be definitively identified through routine clinical diagnosis. Clinical data was collected and genetic diagnosis of HS was confirmed using next-generation sequencing. Statistical analysis was conducted to evaluate the clinical characteristics of children with HS.

Results

A total of thirty children with unexplained anemia were included in the study, resulting in a gene detection diagnostic rate of 80%. This included the identification of five non-HS-related congenital anemia genes (16.66%, 5/30) and nineteen cases of hereditary spherocytosis (HS). Upon initial diagnosis, the clinical features of HS were not significantly distinct compared to other forms of anemia.

Conclusion

In Jiangxi, China, our strategy of genetic screening for these children is feasible after excluding the common causes of anemia, such as nutritional anemia, G-6-PD deficiency, thalassemia, autoimmune hemolytic anemia, and myelopoietic abnormalities in children. This is an exploration to establish a genetic screening strategy for children with HS, and more detailed genetic screening strategies need to be further studied and explored. Next-generation sequencing remains the main method for the diagnosis and differential diagnosis of HS.

Hepatitis C virus infection and Parkinson's disease: insights from a joint sex-stratified BioOptimatics meta-analysis

Hepatitis C virus (HCV) infection poses a significant public health challenge and often leads to long-term health complications and even death. Parkinson's disease (PD) is a progressive neurodegenerative disorder with a proposed viral etiology. HCV infection and PD have been previously suggested to be related. This work aimed to identify potential biomarkers and pathways that may play a role in the joint development of PD and HCV infection. Using BioOptimatics-bioinformatics driven by mathematical global optimization-, 22 publicly available microarray and RNAseq datasets for both diseases were analyzed, focusing on sex-specific differences. Our results revealed that 19 genes, including MT1H, MYOM2, and RPL18, exhibited significant changes in expression in both diseases. Pathway and network analyses stratified by sex indicated that these gene expression changes were enriched in processes related to immune response regulation in females and immune cell activation in males. These findings suggest a potential link between HCV infection and PD, highlighting the importance of further investigation into the underlying mechanisms and potential therapeutic targets involved.

Combined metabolomic and proteomic analysis of sepsis related acute liver injury and its pathogenesis research

BACKGROUND

Sepsis-induced acute liver injury is common in patients in intensive care units. However, the exact mechanism of this condition remains unclear. The purpose of this study was to investigate the roles and mechanisms of proteins and metabolites in the liver tissue of mice after sepsis and elucidate the molecular biological mechanisms of sepsis-related liver injury.

METHODS

First, a lipopolysaccharide (LPS)-induced sepsis mouse model was established. Then, according to alanine aminotransferase (ALT) and aspartate aminotransferase (AST) detection in mouse serum and liver histopathological examination (HE) staining, the septic mice were divided into two groups: acute liver injury after sepsis and nonacute liver injury after sepsis. Metabolomics and proteomic analyses were performed on the liver tissues of the two groups of mice to identify significantly different metabolites and proteins. The metabolomics and proteomics results were further analysed to identify the biological indicators and pathogenesis related to the occurrence and development of sepsis-related acute liver injury at the protein and metabolite levels.

RESULTS

A total of 14 differentially expressed proteins and 46 differentially expressed metabolites were identified. Recombinant Erythrocyte Membrane Protein Band 4.2 (Epb42) and adenosine diphosphate (ADP) may be the key proteins and metabolites responsible for sepsis-related acute liver injury, according to the correlation analysis of proteomics and metabolomics. The expression of the differential protein Epb42 was further verified by western blot (WB) detection.

CONCLUSIONS

Our study suggests that the differential protein Epb42 may be key proteins causing sepsis-associated acute liver injury, providing new and valuable information on the possible mechanism of sepsis-associated acute liver injury.

Hereditary Spherocytosis: Can Next-Generation Sequencing of the Five Most Frequently Affected Genes Replace Time-Consuming Functional Investigations?

Congenital defects of the erythrocyte membrane are common in northern Europe and all over the world. The resulting diseases, for example, hereditary spherocytosis (HS), are often underdiagnosed, partly due to their sometimes mild and asymptomatic courses. In addition to a broad clinical spectrum, this is also due to the occasionally complex diagnostics that are not available to every patient. To test whether next-generation sequencing (NGS) could replace time-consuming spherocytosis-specific functional tests, 22 consecutive patients with suspected red cell membranopathy underwent functional blood tests. We were able to identify the causative genetic defect in all patients with suspected HS who underwent genetic testing (n = 17). The sensitivity of the NGS approach, which tests five genes (ANK1 (gene product: ankyrin1), EPB42 (erythrocyte membrane protein band4.2), SLC4A1 (band3), SPTA1 (α-spectrin), and SPTB (β-spectrin)), was 100% (95% confidence interval: 81.5-100.0%). The major advantage of genetic testing in the paediatric setting is the small amount of blood required (<200 µL), and compared to functional assays, sample stability is not an issue. The combination of medical history, basic laboratory parameters, and an NGS panel with five genes is sufficient for diagnosis in most cases. Only in rare cases, a more comprehensive functional screening is required.