Characterisation of the novel HLA-B*35:593 allele using short and long-read sequencing technologies.

The novel HLA-B*35:593 allele, first described in a potential bone marrow donor from Brazil.

Genomic full-length sequence of the HLA-B*37:46 allele was identified by full length group-specific sequencing.

Genomic full-length sequence of HLA-B*37:46 was identified by a group-specific sequencing approach in a Chinese individual.

Influence of pharmacogenomic polymorphisms on allopurinol-induced cutaneous adverse drug reactions in Thai patients.

BACKGROUND: Allopurinol has been causing substantial morbidity and mortality particularly in Asian population by producing cutaneous adverse drug reactions (cADRs). Nonetheless, there are no data describing whether other genetics are a valid marker for prediction of allopurinol-induced cADRs patients in addition to HLA-B*58:01 allele. The goal of this study was to identify suitable single nucleotide polymorphisms (SNPs) for allopurinol induced cADRs among Thai patients. METHODS: We conducted a case-control association study after enrolling 57 Thai patients with allopurinol induced cADRs and 101 allopurinol-tolerant controls. The genetic biomarkers and associated SNPs located on chromosome 6p21 were examined by TaqMan® SNP genotyping assays in both the cases and the controls. RESULTS: Out of fifteen SNPs in nine genes, we found four combined SNPs (rs3099844 of HCP5, rs9263726 of PSORS1C1, rs9263733 of POLR2LP, and rs9263745 of CCHCR1) were significantly associated with allopurinol-induced cADRs compared to the tolerant controls (OR 73.2; 95% CI 24.2-266.8; P = 1.9 × 10- 24). The overall sensitivity, specificity, positive predictive value and negative predictive value of these combinations were 84%, 94%, 9%, and 100%, respectively. However, the variant alleles of these SNP combinations were detected in 89.5% (51/57) of the cases. Moreover, the HLA-B*58:01 allele was observed in 86.0% of patients with allopurinol-induced cADRs, but only in 4.0% of tolerant controls (OR: 137.2; 95% CI: 38.3-670.5 and p-value = 1.7 × 10- 27). CONCLUSIONS: Thus, this research confirms the association between the specific HLA-B*58:01 allele and all phenotypes of allopurinol-induced cADRs in Thais. Furthermore, there was found the combined four SNPs (rs3099844, rs9263726, rs9263733, and rs9263745) could be used as alternative novel biomarkers for predicting cADRs in patients taking allopurinol.

Characterisation of the novel HLA-B*58:02:04 allele by next-generation sequencing.

HLA-B*58:02:04 differs from HLA-B*58:02:01 by one synonymous nucleotide in codon 215 in exon 4.

Characterization of the novel HLA-B*40:538 allele by next-generation sequencing.

The HLA-B*40:538 allele differs from HLA-B*40:01:02:01 at position 905 C→T in exon 5.

The novel HLA-B*44:48:02 allele characterised by two different sequencing-based typing techniques.

The novel allele HLA-B*44:48:02 differs from HLA-B*44:48:01 by one synonymous nucleotide substitution in exon 3.

Detection of the novel HLA-B*55:01:31, HLA-C*07:1113 alleles and confirmation of HLA-C*12:392.

Novel HLA-B*55:01:31, HLA-C*07:1113 alleles and confirmatory HLA-C*12:392 allele were detected during the HLA typing process.

[HLA genotypes associated with gastrointestinal symptoms in patients with spondyloarthritis without inflammatory bowel disease]. / Genotipos HLA asociados a síntomas gastrointestinales en pacientes con espondiloartritis sin enfermedad inflamatoria intestinal.

OBJECTIVE: This study aimed to establish the association between HLA-A, B, DR genotypes and gastrointestinal variables in patients with SpA without inflammatory bowel disease (IBD). METHODS: Retrospective study of 91 patients with SpA and 401 healthy controls, with typing by Illumina Sequencing/PacBio and LIFECODES HLA-PCR/SSO multiplex sequencing technology. The presence of gastrointestinal symptoms was evaluated by administering a survey, and those who presented 2 or more symptoms were taken for clinical evaluation by rheumatology and gastroenterology, colonoscopy and histopathological study. (Ethics committee approval). RESULTS: The 59,3% of the patients were men, with a mean age of 43,9±11.4 years; 80,2% were classified as ankylosing spondylitis. 14, 28 and 19 genotypes for the HLA-A*, HLA-B* and HLA-DR* loci were identified in both groups, of which a relationship with gastrointestinal symptoms was identified: A*26, A*29 and B*27 were associated to abdominal pain, DRB1*11 and DRB1*16 with abdominal distention, A*30, B*38, DRB1*13 and DRB1*14 with weight loss, B*40 with diarrhea >4 weeks, and presence of mucus in the stools with A*02 and DRB1*11 (p<0.05). Furthermore, the presence of B*15 had a statistical relationship with intolerance to some food, highlighting the B*27 genotype in relation to grains and dairy products, A*23 with grains, vegetables and meats, and B*49 with vegetables and dairy (p<0.05). Regarding the endoscopic variables, macroscopic changes were found in the ileum mucosa related to A*02, B*48, DRB1*14 and the relationship between B*27 and ulcers at this level should be highlighted. Macroscopic changes in the sigmoid colon with B*48 and the rectum with A*30. In microscopic changes, inflammatory alterations of the ileum are mentioned with genotypes DRB1*07, DRB1*13 and DRB1*14, a genotype that is related to changes in the ileum both endoscopically and histologically (p<0.05). CONCLUSIONS: These findings indicate a potential genetic predisposition related to HLA genotypes that may increase the likelihood of food intolerance, gastrointestinal symptoms, and even visible and microscopic changes, specifically in the ileal tissue. The study highlights the presence of B*27 and other noteworthy HLA class I and class II genes (such as DRB1*14) in the diverse Colombian population.

OBJETIVO: Establecer la asociación entre genotipos HLA-A, B, DR y variables gastrointestinales en pacientes con EspA, sin enfermedad inflamatoria intestinal (EII). MÉTODOS: Estudio retrospectivo de 91 pacientes con EspA y 401 controles sanos, con tipificación por tecnología de secuenciación Illumina Sequencing/PacBio, y LIFECODES HLA-PCR/SSO multiplex. Se evaluó la presencia de síntomas gastrointestinales por aplicación de una encuesta, y, aquellos que presentaran dos o más síntomas, fueron llevados a valoración clínica por reumatología y gastroenterología, colonoscopia y estudio histopatológico. (Aprobación del Comité de Ética, HMC, 2022 - 2020). RESULTADOS: El 59,3% de los pacientes fueron hombres, con edad media de 43,9 ± 11,4 años. El 80,2% se clasificó como espondilitis anquilosante. Se identificaron en ambos grupos 14, 28 y 19 genotipos para los loci HLA-A*, HLA-B* y HLA-DR*, de los cuales se identificó relación con síntomas gastrointestinales: A*26, A*29 y B*27, con dolor abdominal; DRB1*11 y DRB1*16, con distensión abdominal; A*30, B*38, DRB1*13 y DRB1*14, con pérdida de peso; B*40, con diarrea >4 semanas y presencia de moco en las deposiciones con A*2 y DRB1*11 (p<0,05). Además, la presencia de B*15, tuvo relación estadística con intolerancia a algún tipo de alimento, a resaltar el genotipo B*27, en relación con granos y lácteos; A*23 con granos, verduras y carnes; y el B*49, con verduras y lácteos (p<0,05). Frente a las variables endoscópicas, se encontraron cambios macroscópicos en la mucosa de íleon relacionados con A*02, B*48, DRB1*14 y, a destacar, la relación B*27 con úlceras a este nivel. Cambios macroscópicos en colon sigmoides con B*48 y en recto con A*30. En cambios microscópicos, se mencionan alteraciones inflamatorias de íleon con genotipos DRB1*07, DRB1*13 y DRB1*14, genotipos que se relaciona a cambios en íleon tanto endoscópica e histológicamente (p<0,05). CONCLUSIONES: Estos resultados sugieren una posible susceptibilidad genética asociada al HLA, con genotipos que pueden predisponer a intolerancia alimentaria, síntomas gastrointestinales, e incluso, a cambios macroscópicos e histológicos, particularmente en tejido de íleon, entre los cuales está presente el B*27, pero resaltan otros interesantes en HLA clase I, como clase II (DRB1*14), en una población de alto mestizaje como la colombiana.

HLA-B and C Expression Contributes to COVID-19 Disease Severity within a South African Cohort.

Globally, SARS-CoV-2 has negatively impacted many lives and industries due to its rapid spread, severe outcomes, and the need for the implementation of lockdown strategies across the world. SARS-CoV-2 disease severity varies among different populations. Host genetics have been associated with various diseases, and their ability to alter disease susceptibility and severity. In addition, Human Leukocyte Antigen (HLA) expression levels and alleles vary significantly among ethnic groups, which might impact the host's response to SARS-CoV-2. Our previous study highlighted that HLA-A might have an effect on COVID-19 disease severity across ethnicities. Therefore, in this study, we aim to examine the effect of HLA-B and C expression levels on COVID-19 disease severity. To achieve this, we used real-time PCR to measure the HLA mRNA expression levels of SARS-CoV-2-infected individuals from a South African cohort and compared them across ethnic groups, disease outcomes, gender, comorbidities, and age. Our results show (1) that the effect of HLA-B mRNA expression levels was associated with differences in disease severity when we compare symptomatic vs. asymptomatic (p < 0.0001). While HLA-C mRNA expression levels were not associated with COVID-19 disease severity. (2) In addition, we observed that HLA-B and HLA-C mRNA expression levels were significantly different between South African Black individuals and South African Indian individuals (p < 0.0001, p < 0.0001). HLA-B mRNA expression levels among symptomatic South African Black individuals were significantly higher than symptomatic South African Indian individuals (p < 0.0001). In addition, the HLA-B mRNA expression levels of symptomatic South African Black individuals were significantly higher than asymptomatic South African Black individuals (p > 0.0001). HLA-C mRNA expression levels among symptomatic South African Black individuals were significantly higher than among symptomatic South African Indian individuals (p = 0.0217). (3) HLA-C expression levels were significantly different between males and females (p = 0.0052). In addition, the HLA-C expression levels of asymptomatic males are higher than asymptomatic females (p = 0.0375). (4) HLA-B expression levels were significantly different between individuals with and without comorbidities (p = 0.0009). In addition, we observed a significant difference between individuals with no comorbidities and non-communicable diseases (p = 0.0034), in particular, hypertension (p = 0.0487). (5) HLA-B expression levels were significantly different between individuals between 26-35 and 56-65 years (p = 0.0380). Our work is expected to strengthen the understanding of the relationship between HLA and COVID-19 by providing insights into HLA-B and C expression levels across ethnic populations in South Africa among COVID-19-symptomatic and asymptomatic individuals. Our results highlight that HLA-B mRNA expression levels contribute to COVID-19 severity as well as variation in ethnicities associated with COVID-19. Further studies are needed to examine the effect of HLA expression levels across various ethnic groups with contributing factors.

Identification of a new HLA-B allele, HLA-B*35:594.

A novel HLA-B*35 allele, officially designated HLA-B*35:594, was identified by next-generation sequencing.

The novel HLA-B*35:01:77 allele identified in a Russian volunteer bone marrow donor.

Nucleotide substitutions in the 5'UTR and exon 2 of HLA-B*35:01:01:05 result in a novel allele, HLA-B*35:01:77.

Identification of the novel HLA-B*13:191 allele by next-generation sequencing.

The novel HLA-B*13:191 allele was detected during the HLA typing for kidney transplantation.

Two novel HLA class I alleles: HLA-A*02:1148 and HLA-B*44:386.

Identification of the novel HLA-A*02:1148 and HLA-B*44:386 alleles by next-generation sequencing.

Novel genetic variants of HLA gene associated with Thai Behcet's disease (BD) patients using next generation sequencing technology.

Behçet's disease (BD) manifests as an autoimmune disorder featuring recurrent ulcers and multi-organ involvement, influenced by genetic factors associated with both HLA and non-HLA genes, including TNF-α and ERAP1. The study investigated the susceptible alleles of both Class I and II molecules of the HLA gene in 56 Thai BD patients and 192 healthy controls through next-generation sequencing using a PacBio kit. The study assessed 56 BD patients, primarily females (58.9%), revealing diverse manifestations including ocular (41.1%), vascular (35.7%), skin (55.4%), CNS (5.4%), and GI system (10.7%) involvement. This study found associations between BD and HLA-A*26:01:01 (OR 3.285, 95% CI 1.135-9.504, P-value 0.028), HLA-B*39:01:01 (OR 6.176, 95% CI 1.428-26.712, P-value 0.015), HLA-B*51:01:01 (OR 3.033, 95% CI 1.135-8.103, P-value 0.027), HLA-B*51:01:02 (OR 6.176, 95% CI 1.428-26.712, P-value 0.015), HLA-C*14:02:01 (OR 3.485, 95% CI 1.339-9.065, P-value 0.01), HLA-DRB1*14:54:01 (OR 1.924, 95% CI 1.051-3.522, P-value 0.034), and HLA-DQB1*05:03:01 (OR 3.00, 95% CI 1.323-6.798, P-value 0.008). However, after Bonferroni correction none of these alleles were found to be associated with BD. In haplotype analysis, we found a strong linkage disequilibrium in HLA-B*51:01:01, HLA-C*14:02:01 (P-value 0.0, Pc-value 0.02). Regarding the phenotype, a significant association was found between HLA-DRB1*14:54:01 (OR 11.67, 95% CI 2.86-47.57, P-value 0.001) and BD with ocular involvement, apart from this, no distinct phenotype-HLA association was documented. In summary, our study identifies specific HLA associations in BD. Although limited by a small sample size, we acknowledge the need for further investigation into HLA relationships with CNS, GI, and neurological phenotypes in the Thai population.

Genomic full-length sequence of the novel HLA-B*56:94 allele.

HLA-B*56:94 differs from HLA-B*56:05:01 by two non-synonymous nucleotide substitutions in exon 1 and synonymous nucleotide substitutions in exon 1 and exon 2.

Rapid and Reliable HLA-B*59:01 Genotyping to Prevent Carbonic Anhydrase Inhibitor-Induced Severe Cutaneous Adverse Reactions.

OBJECTIVE: Carbonic anhydrase inhibitors (CAIs) are intraocular pressure-reducing medications used in ophthalmology. Human leukocyte antigen-B*59:01 (HLA-B*59:01) is strongly associated with CAI-induced severe cutaneous adverse reactions (SCARs). This study aimed to develop and validate a rapid and economical screening method for HLA-B*59:01 to prevent carbonic anhydrase inhibitor-induced SCARs. METHODS: Duplex allele-specific polymerase chain reaction (PCR) with an internal control was performed for HLA-B*59:01 genotyping. The accuracy of duplex allele-specific PCR for HLA-B*59:01 genotyping was evaluated in 200 blood samples, using sequence-based typing (SBT) as the reference method. RESULTS: In total, 50 HLA-B*59:01-positive and 150 HLA-B*59:01-negative results obtained using duplex allele-specific PCR were in complete agreement with the SBT results. CONCLUSION: Duplex allele-specific PCR is a rapid, reliable, and economical assay for screening the HLA-B*59:01 allele.

Detection of two HLA-B*35 variants: HLA-B*35:01:01:39 and -B*35:03:01:32.

Two nucleotide substitutions in intronic regions give rise to the novel alleles: HLA-B*35:01:01:39 and -B*35:03:01:32.

The novel HLA-B*46:01:42 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-B*46:01:42 differs from HLA-B*46:01:01:01 by one nucleotide in exon 5.

Identification of four novel HLA alleles: HLA-B*27:265, -B*35:569, -DRB1*08:117 and -DPB1*1435:01.

Identification of four new HLA alleles (B*27:265, B*35:569, DRB1*08:117, and DPB1*1435:01) in Brazilian bone marrow donors.