02 Allele Research Articles

A splice site variant defining the novel RHD*01(487-3G) allele in trans to RHD*DAR1.2.

A splice site variant defining the novel RHD*01(487-3G) allele in trans to RHD*DAR1.2.

Sacituzumab-govitecan-induced severe acute tubulointerstitial nephritis requiring hemodialysis

BackgroundSacituzumab govitecan is an antibody-drug conjugate that is FDA approved for refractory metastatic triple-negative breast cancer. It targets the human trophoblastic cell-surface antigen 2 (Trop-2) with SN-38, a topoisomerase I inhibitor, attached to the antibody [1]. SN-38 breaks DNA strands and induces tumor apoptosis [2]. Acute kidney injury (AKI) is one of its adverse effects mainly prerenal due to gastrointestinal toxicity, but it has not been reported to cause acute tubulointerstitial nephritis (ATIN).Case PresentationThis report describes a rare adverse effect of sacituzumab govitecan, the approach to diagnosing the etiology of the patient’s AKI, and the mechanism by which sacituzumab govitecan causes ATIN. A woman with metastatic ER positive, PR positive, HER2 negative breast cancer who was initiated on sacituzumab govitecan presents with vomiting and diarrhea, and findings of nephrotic-range proteinuria, negative anti-PLA2R antibody, and severe AKI requiring hemodialysis. She underwent kidney biopsy and pathology showed ATIN characterized by patchy interstitial inflammation alongside tubular injury without glomerular and vascular involvement. With intermittent renal replacement therapy, furosemide challenge, and a course of prednisone, the patient’s kidney function recovered.ConclusionsSacituzumab has a high affinity for Trop-2 protein which is also expressed within the collecting ducts, and to a lesser extent, the proximal tubule. Individuals, such as this patient, who express a homozygous genotype for UGT1A1*28 allele are at increased risk for AKI from sacituzumab govitecan due to decreased glucuronidation of SN-38.

HLA-DRB1*01 predicts treatment outcome in juvenile idiopathic arthritis: A retrospective-prospective cohort study.

Juvenile idiopathic arthritis (JIA) is the most common chronic inflammatory autoimmune disease in childhood, significantly contributing to both short- and long-term disability. While certain human leukocyte antigen (HLA) class II alleles are known to be associated with specific subgroups of JIA, emerging evidence suggests a strong correlation between these alleles and treatment response. This study involved 143 JIA patients diagnosed according to International League of Associations for Rheumatology criteria. Each patient underwent HLA class II typing, including HLA-B27, as well as tests for rheumatoid factor (RF) and antinuclear antibodies (ANA). Comprehensive rheumatological assessments were conducted at diagnosis, with follow-ups at three and six months post-onset. After six months of methotrexate (MTX) treatment, patients were categorized as responders or non-responders. Responders achieved clinically inactive disease based on the American College of Rheumatology Provisional Criteria for Defining Clinical Inactive Disease and Clinical Remission. Non-responders, who did not reach clinically inactive disease after six months of treatment, required the addition of another non-biological disease-modifying antirheumatic drug (DMARD) or a biological DMARD. Our analysis revealed that the HLA-DRB1*01 allele is a significant prognostic marker for therapeutic response, predicting therapeutic resistance (P=0.01). The most prevalent HLA-DRB1 alleles in the treatment-resistant group were HLA-DRB1*08:11 (11.3%), HLA-DRB1*01:01 (8.5%), HLA-DRB1*01:13, HLA-DRB1*04:11 (7%), HLA-DRB1*08:13, and HLA-DRB1*08:15 (4.2%). These findings highlight the critical role of HLA class II alleles in pediatric rheumatology, particularly in relation to treatment response and disease prognosis. In the era of personalized medicine, understanding the genetic contributions to treatment response and outcomes in JIA patients is essential. A key limitation of this study was the lack of comparison of treatment responses across different JIA subtypes. Future studies should prioritize evaluating MTX efficacy within specific JIA subgroups to enable a more tailored understanding of its effectiveness.

Sequence analysis and identification of a novel HLA-DPB1*02:01:69 allele by third-generation sequencing

To analyze the sequence of a novel HLA-DPB1 allele in an individual. A individual identified from the database of blood donors for matched platelet transfusion at the Blood Center of Zhejiang Province in May 2022 was selected as the study subject. HLA genotype of the individual was determined by next-generation sequencing (NGS) on an Ion Torrent S5 platform. The sequence of the HLA-DPB1 locus was also determined by NGS on an Illumina Miseq platform and third-generation sequencing using Oxford Nanopore MinION. This study was approved by the Blood Center of Zhejiang Province (Ethics No. 2021-001). A novel HLA-DPB1*02 allele was identified in the specimen, for which the closest genotype was HLA-DPB1*02:new,17:01:01G, with the variant located in exon 3. Meanwhile, the NGS also revealed a novel HLA-DPB1*17 allele, with the closest genotype being HLA-DPB1*02:01,17:new. Both the HLA-DPB1*17:01:01:01 and HLA-DPB1*02 alleles were identified by third-generation sequencing. Compared with the HLA-DPB1*02:01:02:01 allele, the novel allele had a G>A variation at position 369 in the exon 3, which however did not result in amino acid change. A novel HLA-DPB1 allele has been identified and validated by both NGS and TGS, which has been named as HLA-DPB1*02:01:69 by the World Health Organization Committee on Nomenclature of Factors of the HLA System.

Characterisation of the HLA-DQ alpha eplet 52SK targeting the DQA1*01 alleles family.

Eplet 52SK is unique in the HLA eplet registry as targeting the whole family of DQA1*01 alleles. It is proposed as an antibody-verified eplet but has not been validated enough to deserve this label. Especially, confusion can occur with reactivity targeting the 52PQ eplet which is present on the DQB1*05 and DQB1*06 alleles families, as DQ molecule stability imposes DQA1*01 to selectively associate with these DQ-β families only. Using two Luminex single antigen (LSA) assays from two vendors, beads bearing DR-α/DQ6 heterodimers, a special build LSA panel of additional DQ beads, and an adsorption/elution strategy relying on cells from deceased donors or recombinant cells solely expressing one DQ antigen, we definitely established the antibody-verified status of eplet 52SK using patients' sera reacting only against the DQ5 and DQ6 beads of the One Lambda LSA panel in routine patients' follow up. We also show that reactivity against this eplet is not a rare event among anti-DQ1 immunisation. This study further strengthens the importance of considering the DQA1 locus in immunological studies of HLA and in organ allocation strategies.

Frequency and relationship of HLA allele in Turkish patients with Fanconi anemia

Purpose: Fanconi anemia (FA) is a childhood disorder inherited in an autosomal recessive manner. It is characterized by bone marrow failure, a range of congenital physical abnormalities, increased susceptibility to cancer, chromosomal instability, and heightened sensitivity to cross-linking agents. The aim of this study was to determine the role of the HLA Class I and Class II alleles in genetic susceptibility to Fanconi anemia in Turkish patients. Materials and Methods: In this study, we retrospectively evaluated the HLA-A, -B, and -DRB1 allele frequencies of patients with Fanconi anemia who underwent hematopoietic stem cell transplantation between 2010 and 2021. HLA-A, -B, -DR of all patients and healthy Turkish individuals were genotyped. Results: The study included 86 patients with Fanconi anemia and 300 healthy controls. The most common antigens in patients with Fanconi were HLA-A*02, HLA-B*35 and DRB1*11. Moreover, in the patient group, the HLA-A*23 allele was significantly lower than the control group. When we evaluated the patient group according to gender the HLA-A*01 allele was significantly higher in the female patient group. Conclusion: Our study provides valuable insights into the genetic susceptibility of Turkish patients with Fanconi anemia, focusing on the role of HLA Class I and Class II alleles. HLA-B*14 may be a risk factor and HLA-A*23 may be protective for Fanconi anemia. These results contribute to our understanding of the complex genetic factors underlying Fanconi anemia and may have implications for improved diagnosis, prognosis, and potential therapeutic interventions for affected individuals.

Identification of HLA alleles involved in immune thrombotic thrombocytopenic purpura patients from Turkey.

Thrombotic thrombocytopenic purpura (TTP) is one of the rare group disorders classified as thrombotic microangiopathies (TMAs). Approximately 90% of TTP developed immune-mediation by the formation of antibodies against the enzyme ADAMTS-13. The exact cause is unknown. To establish an association between human leukocyte antigen (HLA) and autoimmune basis, as susceptibility or protection against the disease, we contributed a study aiming to evaluate the role of HLA in immune-mediated TTP (iTTP). Considering epidemiological factors such as age, sex, ethnicity, and geographical origins, we contributed the study in our country, Turkey, which consist of a very heterogeneous population. Patients' data collection was retrospectively from electronic database on two University hospitals having big therapeutic apheresis service. Control arm was healthy people registered as stem cell donors matched in terms of age and sex. The frequency of HLA-DRB1 and HLA-DQB1 alleles between acquired TTP and the control group was compared using the chi-square method. Yates correction and logistic regression were performed on these results. A total of 75 iTTP patients and 150 healthy individuals enrolled to the study. HLA-DRB1∗11, HLA-DQB1∗03, HLA-DRB1∗11:01, HLA-DRB1∗14:01, HLA-DRB1∗13:05, HLA-DRB1∗11 + HLA-DQB1∗03 allele pair and HLA-DRB1∗15 + HLA- DQB1∗06 were proved to be susceptibility allele pairs for iTTP. HLA-DRB1∗15, HLA-DRB1∗01:01, HLA-DRB1∗07:01, HLA-DRB1∗13:01, HLA-DRB1∗14:54, HLA-DQB1∗05:01, HLA-DQB1∗02:02 and HLA-DRB1∗07 + HLA-DQB1∗02 allele pair were found to be protective against iTTP. Our findings support an association with iTTP across very heterogenous populations in Turkey.

Association of human leukocyte antigen (HLA) status with immune checkpoint inhibitor (ICI) pneumonitis in patients with non-small cell lung cancer (NSCLC).

8620 Background: Pneumonitis is a potentially serious complication occurring in 5-20% of lung cancer patients receiving ICI. The genetic risk factors for ICI pneumonitis are unclear. Given the association between HLA genetic variants and autoimmune diseases, we hypothesized that certain HLA genetic variants are associated with risk of ICI pneumonitis. Methods: Patients with advanced EGFR/ ALK wild type, PD-L1 tumor proportion score ≥50% NSCLC who received ICI were enrolled from year 2019 to 2022. Germline HLA typing was performed on buccal swab specimens using the Alltype Fastplex assay. Clinicopathological characteristics, treatment courses and survival outcomes were retrospectively collated. The primary endpoint was the correlation of common HLA variants (present in >30% of subjects) to the risk of ICI pneumonitis. Results: 42 patients (all Chinese, 36 male, 33 current/former smokers) were enrolled. Median age was 71 years old (range 51-91). 34, 6, 1 and 1 patients had adenocarcinoma, NSCLC not otherwise specified, squamous cell carcinoma and large cell neuroendocrine carcinoma respectively. Majority (33/42, 79%) received pembrolizumab monotherapy while 9 (21%) patients received pembrolizumab plus chemotherapy. Median follow up time was 27.8 months. At data cutoff, 28 (67%) patients received ICI for more than 1 year and 10 (24%) patients stopped ICI after completion of 2-year course of treatment. Seven (17%) patients developed pneumonitis, of which 3 were grade 2 and 4 were grade 3 in severity. Median time to development of pneumonitis was 6.9 months (range 0.3-25.2). Demographic characteristics were similar between patients who did or did not experience pneumonitis. In the entire cohort, twenty-two (52%) patients harbored the class II DPB1*02 allele. This allele was significantly associated with development of ICI pneumonitis. All 7 patients who had ICI pneumonitis harbored the DPB1*02 allele. The incidence of pneumonitis in patients harboring the DPB1*02 allele was 32% compared to 0% in those without this allele (p=0.009). Patients who experienced pneumonitis had worse survival rates than those without (p=0.03), but expression of DPB1*02 allele was not associated with inferior survival outcomes. Conclusions: Our results suggested that expression of DPB1*02 allele may be associated with development of ICI pneumonitis. A larger case-control study is ongoing to validate this association. [Table: see text]

Improving ethnic and racial diversity in biomarker-driven clinical trials: A proof of concept with the BASECAMP-1 master prescreening study of patients with high-risk solid tumors with human leukocyte antigen-A*02 (HLA-A*02) loss of heterozygosity (LOH).

1604 Background: Diversity in clinical studies is essential to address health disparities, but racial and ethnic minorities are often underrepresented in clinical studies, especially in precision medicine studies using genetic data (1). BASECAMP-1 (NCT04981119) is an ongoing prescreening study to identify patients with unresectable advanced or metastatic solid tumors and tumor-associated HLA-A*02 LOH for the EVEREST-1 and -2 Tmod chimeric antigen receptor T-cell therapy trials. When enrollment began in 2021, eligibility for Part 1 was restricted to patients with germline HLA-A*02:01 based on preclinical data. Additional analysis revealed the blocker in the Tmod construct had activity across HLA-A*02 subtypes (Mock, et al. Mol Ther Oncolytics.2022). Eligibility for Part 1 was then expanded to all HLA-A*02 subtypes, allowing enrollment of more diverse patient populations. HLA-A*02 allele subtypes vary by ethnicity and race; the frequency of HLA-A*02:01 is 96% in non-Hispanic Whites, but ranges from 53% to 73% in other ethnicities and races. The frequency of all other HLA-A*02 allele subtypes (HLA-A*02:XX) is <5% in non-Hispanic Whites but up to 66% in other ethnicities and races (2,3). Methods: Patients eligible for BASECAMP-1 were identified at United States study sites. All patients screened before January 16, 2024, for Part 1 were included for demographic and central lab HLA-A typing. The % increase in eligibility and % of heterozygous HLA-A*02 patients with HLA-A*02:XX were calculated by ethnicity and race. Results: A total of 1124 patients were screened for germline HLA-A*02 typing; 431 patients were HLA-A*02:01 heterozygous, of whom 37 (9%) were Hispanic, 14 (3%) African American (AA), 2 (<1%) American Indian or Alaska Native, 17 (4%) Asian or Pacific Islander (API), and 324 (75%) non-Hispanic White (Table). The eligibility expansion identified 62 patients with HLA-A*02:XX heterozygosity, of whom 6 (10%) were Hispanic, 6 (10%) AA, 19 (31%) API, and 25 (40%) non-Hispanic White. Conclusions: By expanding enrollment to include HLA-A*02:XX, 16% more Hispanic, 43% more AA, and 112% more API patients were identified, improving the diversity in this trial compared with that of initial enrollment. 1. Aldrighetti, et al. JAMA Netw Open 2021. 2. Ellis, et al. Human Immunol. 2000. 3. Gragert, et al. Human Immunol.2013. Clinical trial information: NCT04981119 . [Table: see text]

Genetic profile of RHCE, Kell, Duffy, Kidd, Diego and MNS hybrid glycophorins blood groups in ethnic northeastern Thais: Alleles, genotypes and risk of alloimmunisation.

Antibodies against blood group antigens play a key role in the pathophysiology of haemolytic transfusion reactions (HTRs) and haemolytic disease of the fetus and newborn (HDFN). This study aimed to determine the frequencies of alleles, genotypes, and risk of alloimmunisation of clinically significant blood group systems in ethnic northeastern Thais. In total, 345 unrelated, healthy, ethnic northeastern Thais were tested using the in-house PCR-sequence specific primers (PCR-SSP) method for simultaneously genotyping of RHCE, Kell, Duffy, Kidd, Diego and MNS glycophorin hybrids and results confirmed by Sanger sequencing. In this cohort, the alleles RHCE*C (81.0%) and RHCE*e (84.8%) were more prevalent than RHCE*c (19.0%) and RHCE*E (15.2%). The most common predicted haplotype combinations of the RHCE alleles were C+c-E-e+(R1R1) (59.4%) followed by the C+c+E+e+ (R1R2) (20.6%) and C+c+E-e+ (R1r) (11.3%). The KEL*01 allele was not found in this study. The frequencies of FY*01 and FY*02 were 88.3% and 11.7%, respectively. The genotype FY*02/02 was found in four samples (1.2%). The frequencies of JK*01 and JK*02 were 52.5% and 47.5%, respectively. Homozygous JK*02/02 was found in 81 samples (23.5%). The frequencies of DI*01 and DI*02 were 0.6% and 99.4%, respectively. In total, 64 samples (18.6%) were found to carry the MNS glycophorin hybrids. Our results indicated a possible high risk of c, E, Fyb, Jka, Jkb and Mia alloimmunisation in these populations. Moreover, methods established for genotyping clinically significant blood groups in this study can now be utilised in routine clinical application.

Identifying MAGE-A4-positive tumors for TCR T cell therapies in HLA-A∗02-eligible patients

T cell receptor (TCR) Tcell therapies target tumor antigens in a human leukocyte antigen (HLA)-restricted manner. Biomarker-defined therapies require validation of assays suitable for determination of patient eligibility. For clinical trials evaluating TCRTcell therapies targeting melanoma-associated antigen A4(MAGE-A4), screening in studies NCT02636855 and NCT04044768 assesses patient eligibility based on: (1) high-resolution HLA typing and (2) tumor MAGE-A4 testing via an immunohistochemical assay in HLA-eligible patients. The HLA/MAGE-A4 assays validation, biomarker data, and their relationship to covariates (demographics, cancer type, histopathology, tissue location) are reported here. HLA-A∗02 eligibility was 44.8% (2,959/6,606) in patients from 43 sites across North America and Europe. While HLA-A∗02:01 was the most frequent HLA-A∗02 allele, others (A∗02:02, A∗02:03, A∗02:06) considerably increased HLA eligibility in Hispanic, Black, and Asian populations. Overall, MAGE-A4 prevalence based on clinical trial enrollment was 26% (447/1,750) across 10 solid tumor types, and was highest in synovial sarcoma (70%) and lowest in gastric cancer (9%). The covariates were generally not associated with MAGE-A4 expression, except for patient age in ovarian cancer and histology in non-small cell lung cancer. This report shows the eligibility rate from biomarker screening for TCR Tcell therapies and provides epidemiological data for future clinical development of MAGE-A4-targeted therapies.

Impact of human leucocyte antigen class II polymorphism on anti-red blood cell antibody development: Correlations and indications.

Blood transfusion therapy is vital for many patient groups. They can cause many complications, and the development of anti-red blood cell (RBC) antibodies is of significant importance. Molecules of class II human leucocyte antigens (HLA) are one of the several factors that influence antibody development in patients. In this study, we investigated 108 patients who developed antibodies against different erythrocyte antigens and 115 patients on multiple transfusion therapies who did not develop anti-RBC antibodies. The HLA loci HLA-DRB1 and HLA-DQB1 were typed using commercial molecular assays routinely used in HLA laboratories. An increased frequency of the HLA-DRB1*04 allele group was observed in patients who developed antibodies. Additionally, HLA-DRB1*09 was also significant for anti-E development and in patients with multi-specific alloimmunization. It was found that the HLA-DRB1*07 allele group is associated with antibodies to antigents of the Rh and MNS systems but also lacks an association with anti-K development. The HLA-DRB1*11 and -DRB1*01 allele groups displayed a protective mechanism for anti-E development, similar to that of HLA-DQB1*02 for anti-K. There is an association between various HLA class II alleles and anti-RBC development.

Molecular Screening of VEL*01N.01 and AUG*02 Alleles in Indian Population: Towards Identifying Rare Blood Donors.

Molecular Screening of VEL*01N.01 and AUG*02 Alleles in Indian Population: Towards Identifying Rare Blood Donors.

Uncoupling of Cytochrome P450 2B6 and stimulation of reactive oxygen species production in pharmacogenomic alleles affected by interethnic variability

Cytochrome P450 mediated substrate metabolism is generally characterized by the formation of reactive intermediates. In vitro and in vivo reaction uncoupling, results in the accumulation and dissociation of reactive intermediates, leading to increased ROS formation. The susceptibility towards uncoupling and altered metabolic activity is partly modulated by pharmacogenomic alleles resulting in amino acid substitutions. A large variability in the prevalence of these alleles has been demonstrated in CYP2B6, with some being predominantly unique to African populations.The aim of this study is to characterize the uncoupling potential of recombinant CYP2B6*1, CYP2B6*6 and CYP2B6*34 metabolism of specific substrates.Therefore, functional effects of these alterations on enzyme activity were determined by quantification of bupropion, efavirenz and ketamine biotransformation using HPLC-MS/MS. Determination of H2O2 levels was performed by the AmplexRed/horseradish peroxidase assay.Our studies of the amino acid substitutions Q172H, K262R and R487S revealed an exclusive use of the peroxide shunt for the metabolism of bupropion and ketamine by CYP2B6*K262R. Ketamine was also identified as a trigger for the peroxide shunt in CYP2B6*1 and all variants. Concurrently, ketamine acted as an uncoupler for all enzymes. We further showed that the expressed CYP2B6*34 allele results in the highest H2O2 formation.We therefore conclude that the reaction uncoupling and peroxide shunt are directly linked and can be substrate specifically induced with K262R carriers being most likely to use the peroxide shunt and R487S carrier being most prone to reaction uncoupling. This elucidates the functional diversity of pharmacogenomics in drug metabolism and safety.

Saliva direct PCR protocol for HLA-DQB1*02 genotyping.

Celiac disease (CD) is an immune disorder, that is triggered by gluten ingestion in genetically predisposed individuals. The HLA-DQB1*02 allele is the main predisposing genetic factor and a candidate for first-line genotyping screening. We designed and validated a simple, DNA purification-free PCR protocol directly from crude saliva, enabling the detection of the DQB1*02 allele. This assay also distinguishes homozygous from heterozygous carriers. We propose this method for use in mass screening and/or epidemiological studies.

Rare occurrence of RHD null alleles with Del expression among serologically D-negative blood donors

Background/Aim: An investigation into the diversity of serologically D-negative blood donors in the Republic of Srpska entity of Bosnia and Herzegovina forms the basis of this research. The primary purpose of the study was the examination of RHD variants over a period of five years. Methods: A comprehensive depiction of the RHD distribution in D-negative blood donors is achieved through a combination of serological observations and DNA testing (PCR-SSP with fluorometric signal detection), involving 74,149 blood donors. The adsorption/elution method was used to confirm the Del phenotype. Results: A small fraction (0.31 %) of the serologically D-negative blood donors was found to contain eight different RHD alleles. The Del phenotype of the RHD*01N.03 and RHD*01EL.44 alleles was highlighted, challenging the common perception that these alleles are associated exclusively with a D-negative expression. Conclusion: The importance of molecular methods in analysing and understanding Del variants, which typically elude conventional serological assays , is underscored by the findings. A group of donors seemingly having the RHD*01 allele but who lacked D antigen expression was encountered, hinting at the potential presence of still unidentified, possibly geographically restricted, RHD variants or alterations in other genes responsible for the expression of Rh proteins in the erythrocyte membrane.

Effect of CYP3A4*22, CYP3A5*3 and POR*28 genetic polymorphisms on calcineurin inhibitors dose requirements in early phase renal transplant patients.

This study aimed to investigate the combined effect of CYP3A5*3, CYP3A4*22, and POR*28 genetic polymorphisms on tacrolimus and cyclosporine dose requirements. One hundred thirty renal transplant patients placed on either tacrolimus or cyclosporine were recruited, where the effect of CYP3A5*3, CYP3A4*22, and POR*28 genetic polymorphisms on their dose requirements were studied at days 14, 30, and 90 post-transplantations. The POR*28 allele frequency in the studied population was 29.61%. The tacrolimus dose-adjusted trough concentration ratio (C0/D) was significantly lower in the fast metabolizers group ( CYP3A5*1/POR*28(CT/TT ) carriers) than in the poor metabolizers group ( CYP3A5*3/*3/CYP3A4*22 carriers) throughout the study (14, 30, and 90 days) ( P = 0.001, <0.001, and 0.003, respectively). Meanwhile, there was no significant effect of this gene combination on cyclosporine C0/D. Combining the CYP3A5*3, POR*28 , and CYP3A4*22 genotypes can have a significant effect on early tacrolimus dose requirements determination and adjustments. However, it does not have such influence on cyclosporine dose requirements.

A change in risk assessment for treatment with statins in patients with familial hypercholesteremia and Gilbert's syndrome

Abstract Background Gilbert’s Syndrome (GS) is a heredity disease that mildly increases serum unconjugated bilirubin. GS is usually asymptomatic and considered to be benign. It is postulated to be present in 10-16% of the population but the exact incidence is unknown since it is usually an incidental finding that goes under diagnosed and under-reported. Conversely, heterozygous familial (FH) hypercholesteremia, estimated to be present in 1 in 250, is responsible for significant morbidity and mortality and never ignored. Patients with FH are especially at risk for atherosclerotic cardiovascular disease (ASCVD) due to the cumulative effect of high cholesterol starting at a young age. Recent studies report that mildly elevated serum bilirubin (especially the UGT1A1*28 allele), in patients with concurrent GS and FH, is protective against ASCVD. The deleterious effect of one liver mutation may be offset by the beneficial effect of the second mutation resulting in an inverse relationship between the two diseases. Due to that association, statins may be contraindicated in patients with concurrent FH and GH because they are more susceptible to toxicity and adverse events. Purpose Patients with coexisting FH and GS are postulated to have innate cardioprotection and therefore, treatment with statins may be unnecessary and should be avoided due to an increased risk for drug toxicity and intolerable adverse events. Methods This was a systematic review of 31 peer-reviewed publications identified by using databases: EBSCO Discovery, World Cat, PubMed, OVID, Google Scholar, Springer, Theime, Elsevier, Science Direct, and Cochrane Collaboration. Publications ranged from 2006-2021 and included subjects ages 18-80 and bench studies using Gunn rats. The quality of evidence was analyzed and evaluated. Results Recent retrospective and prospective studies indicate that mildly elevated serum bilirubin, in patients with concurrent GS and FH, is protective against ASCVD. Consequently, this population may not need statin therapy and may be more susceptible to statin toxicity and intolerable adverse events. Conclusion GS is postulated be innately cardioprotective for ASCVD. The identification of patients with concurrent FH and GS is not mainstream and is overdue. These are not uncommon diseases and their co-existence has been underestimated because GS is considered benign and underreported. The potential exists for patients with FH and silent Gilbert’s Syndrome to be overtreated or unnecessarily treated with statins. Medications that inhibit UDP-glucuronosyltranferase-enzyme activity and UG1A1 mediated glucuronidation may lead to toxicity and intolerable adverse events. Studies have shown an adverse relationship between statins and increased bilirubin. It is recommended that both FH and Gilbert’s Syndrome be routinely screened for in pediatric and adult populations, especially prior to statin prescribing.

Application of a simplified PCR-SSP method to detect A4GALT*01 and A4GALT*02 typing among Thai blood donors.

An intronic A4GALT single nucleotide variant, rs5751348:G>T, P2 or A4GALT*02 allele has a lower level of the enzyme-encoding A4GALT transcripts than the P1 individuals. Here, we first develop and validate a simple inhouse PCR-SSP method to detect A4GALT*01 and A4GALT*02 alleles, and second, apply this method to compare the allele frequencies between Thai and other populations. The conventional test tube technique was used to detect the P1 antigen in 222 blood samples from Thai blood donors at Thammasat University Hospital. A PCR-SSP method was optimized and validated for reproducibility and specificity to identify these alleles and was subsequently tested on 1,840 DNA samples of unknown phenotypes obtained from central, northern and southern Thais. In addition, allele frequencies of central Thais were compared with those of other populations. In the tested cohort (n=222), P1 and P2 phenotypes were typed in 26.13 and 73.87% of donors, respectively. The developed PCR-SSP was successfully optimized, and the outcomes were consistent with those of serological phenotyping and DNA sequencing results, demonstrating its validity for predicting P1/P2 phenotype. For central, northern and southern Thais, the A4GALT*01 frequency was 0.1579 (430/2,724), 0.1183 (71/600), and 0.2575 (206/800), whereas the A4GALT*02 frequency was 0.8421 (2,294/2,724), 0.8817 (529/600), and 0.7425 (594/800), respectively. Their observed frequencies among central Thais significantly differed from those in other populations (p<0.05). Our study has successfully developed a simple, precise, and reliable method to genotype A4GALT*01 and A4GALT*02 using inhouse developed PCR-SSP for predicting P1/P2 status.

Distinct HLA associations with autoantibody-defined subgroups in idiopathic inflammatory myopathies

In patients with idiopathic inflammatory myopathies (IIM), autoantibodies are associated with specific clinical phenotypes suggesting a pathogenic role of adaptive immunity. We explored if autoantibody profiles are associated with specific HLA genetic variants and clinical manifestations in IIM. We included 1348 IIM patients and determined the occurrence of 14 myositis-specific or -associated autoantibodies. We used unsupervised cluster analysis to identify autoantibody-defined subgroups and logistic regression to estimate associations with clinical manifestations, HLA-DRB1, HLA-DQA1, HLA-DQB1 alleles, and amino acids imputed from genetic information of HLA class II and I molecules. We identified eight subgroups with the following dominant autoantibodies: anti-Ro52, -U1RNP, -PM/Scl, -Mi2, -Jo1, -Jo1/Ro52, -TIF1γ or negative for all analysed autoantibodies. Associations with HLA-DRB1∗11, HLA-DRB1∗15, HLA-DQA1∗03, and HLA-DQB1∗03 were present in the anti-U1RNP-dominated subgroup. HLA-DRB1∗03, HLA-DQA1∗05, and HLA-DQB1∗02 alleles were overrepresented in the anti-PM/Scl and anti-Jo1/Ro52-dominated subgroups. HLA-DRB1∗16, HLA-DRB1∗07 alleles were most frequent in anti-Mi2 and HLA-DRB1∗01 and HLA-DRB1∗07 alleles in the anti-TIF1γ subgroup. The HLA-DRB1∗13, HLA-DQA1∗01 and HLA-DQB1∗06 alleles were overrepresented in the negative subgroup. Significant signals from variations in class I molecules were detected in the subgroups dominated by anti-Mi2, anti-Jo1/Ro52, anti-TIF1γ, and the negative subgroup. Distinct HLA class II and I associations were observed for almost all autoantibody-defined subgroups. The associations support autoantibody profiles use for classifying IIM which would likely reflect underlying pathogenic mechanisms better than classifications based on clinical symptoms and/or histopathological features. See a detailed list of funding bodies in the Acknowledgements section at the end of the manuscript.