ABSTRACTKawasaki disease (KD), also known as mucocutaneous lymph node syndrome, is a leading cause of vasculitis in children aged < 5 years. The HLA complex has been investigated for its association with KD since 1978 without conclusive results due to limitations such as small sample sizes. This study aimed to evaluate the associations and genetic linkage between HLA‐DRB1 and KD, as well as its complications. The case‐control and family‐based studies enrolled 795 patients with KD and 946 healthy controls. Of the 795 patients, 180 trios were included. Genotypes of HLA‐DRB1 were identified by sequence‐based typing according to the International ImMunoGeneTics database. Allele frequencies were calculated using PyPop 7.0. The transmission/disequilibrium test (TDT) was used to verify the genetic linkage between HLA‐DRB1 and KD. HLA‐DRB1*15:01 was significantly associated with KD (OR, 1.44, Pc = 0.03) and with KD without CALs (OR = 1.46, Pc = 0.04). HLA‐DRB1*14:01 was a risk factor for KD with CALs (OR = 2.47, Pc = 0.004) whereas HLA‐DRB1*12:02 was a protective factor against CALs (OR = 0.49, Pc = 0.01). In the family‐based study, HLA‐DRB1*15:01 demonstrated significant overtransmission to KD patients (OR = 3.35; 95% CI, 2.20–5.78; Pc = 1.19E‐06) and to KD patients without CALs (OR = 4.42; 95% CI, 2.59–10.08; Pc = 6.24E‐06). The overtransmission remained significant in male KD patients (OR = 2.81; 95% CI, 1.68–5.58; Pc = 0.003), and in male KD patients without CALs (OR = 3.22; 95% CI, 1.69–8.84; Pc = 0.02). Our study identified significant associations between HLA‐DRB1*15:01, *14:01, and *12:02 with KD. The association between HLA‐DRB1*15:01 and KD was further verified by TDT, indicating a genetic linkage between the HLA‐DRB1 locus and KD susceptibility.

The novel HLA-C*05:01:74 allele differs from C*05:01:01:01 by a single synonymous substitution in exon 4.

HLA-A*23:23:02 differs from the most closely related allele A*23:23:01 by a single synonymous substitution in exon 3.

ABSTRACTBK polyomavirus (BKPyV) and Cytomegalovirus (CMV) often replicate after kidney transplantation, with management limited to reducing immunosuppression and risking rejection. Among genetic factors that may modulate the antiviral response, HLA evolutionary divergence (HED, allowing a greater diversity of antigen presentation) and the HLA‐B leader dimorphism (MM, MT, TT, influencing NK cell–mediated immunity) are interesting. We aimed to compare these parameters between patients who experienced viral replication within the first post‐transplant year and those who did not. We analysed 306 kidney transplants performed between 2019 and 2023 at Amiens University Hospital. HLA typing was performed in recipients and donors to determine HED (loci A, B, C, DRB1, DQB1) and HLA‐B leader dimorphism. 22.5% of the recipients (69/306) developed BKPyV possible nephropathy (defined by urinary PCR > 7 log10 copies/mL or DNAemia) and 40.2% (123/306) developed CMV infection during the first year. In a multivariate analysis, a donor–recipient HLA‐B leader mismatch was protective against BKPyV replication (OR = 0.48; p = 0.02), whereas no similar association was observed for CMV replication (OR = 1.42; p = 0.169). HLA‐B leader dimorphism could serve as a predictor of BKPyV replication risk, if confirmed in independent cohorts.

HLA-C*07:1193 differs from HLA-C*07:02:01:03 in exon 5 codon 292 (GCT>GTT).

One nucleotide substitution in codon 163 of HLA-C*03:04:01:01 results in a novel allele HLA-C*03:98.

HLA-A*32:187 differs from HLA-A*32:01:01:01 by one nucleotide substitution in codon 211 in exon 4.

The novel allele HLA-B*58:01:46 differs from HLA-B*58:01:01:03 by a single nucleotide substitution in codon 49 GCG → GCC in exon 2.

The novel alleles HLA-A*11:01:01:94 and HLA-C*15:02:01:68 were identified during routine HLA typing.

HLA-DPB1*1790:01 differs from HLA-DPB1*02:02:01:01 by a single non-synonymous nucleotide change in exon 2.