Characterisation of the novel HLA-C*01:273 allele, first identified in a Brazilian individual.

The novel HLA-C*01:273 allele, first described in a potential bone marrow donor from Brazil.

The novel HLA-C*04:01:01:182 allele identified in a candidate bone marrow donor by next-generation sequencing.

HLA-C*04:01:01:182 differs from the HLA-C*04:01:01:06 allele by one nucleotide substitution in the 5'UTR.

The novel HLA-C*14:02:01:31 allele identified in a candidate bone marrow donor by next-generation sequencing.

Characterisation of the novel HLA-C*14:02:01:31 allele in a 21-year-old Greek bone marrow donor.

Identification of the new allele HLA-C*04:01:01:186 in a Greek individual using next generation sequencing.

The newly discovered HLA-C*04:01:01:186 allele differs from HLA-C*04:01:01:01 by a single nucleotide substitution in intron 3.

Common and rare genetic variants predisposing females to unexplained recurrent pregnancy loss.

Recurrent pregnancy loss (RPL) is a major reproductive health issue with multifactorial causes, affecting 2.6% of all pregnancies worldwide. Nearly half of the RPL cases lack clinically identifiable causes (e.g., antiphospholipid syndrome, uterine anomalies, and parental chromosomal abnormalities), referred to as unexplained RPL (uRPL). Here, we perform a genome-wide association study focusing on uRPL in 1,728 cases and 24,315 female controls of Japanese ancestry. We detect significant associations in the major histocompatibility complex (MHC) region at 6p21 (lead variant=rs9263738; P = 1.4 × 10-10; odds ratio [OR] = 1.51 [95% CI: 1.33-1.72]; risk allele frequency = 0.871). The MHC associations are fine-mapped to the classical HLA alleles, HLA-C*12:02, HLA-B*52:01, and HLA-DRB1*15:02 (P = 1.1 × 10-10, 1.5 × 10-10, and 1.2 × 10-9, respectively), which constitute a population-specific common long-range haplotype with a protective effect (P = 2.8 × 10-10; OR = 0.65 [95% CI: 0.57-0.75]; haplotype frequency=0.108). Genome-wide copy-number variation (CNV) calling demonstrates rare predicted loss-of-function (pLoF) variants of the cadherin-11 gene (CDH11) conferring the risk of uRPL (P = 1.3 × 10-4; OR = 3.29 [95% CI: 1.78-5.76]). Our study highlights the importance of reproductive immunology and rare variants in the uRPL etiology.

[Genetic study of a rare Chinese pedigree with a recombination occurring between the HLA-A/C loci in both parents].

OBJECTIVE: To analyze a Chinese pedigree with a recombination occurring between the HLA-A/C loci in both parents. METHODS: A patient who was planning to undergo hematopoietic stem cell transplantation due to "aplastic anemia" in February 2022 was selected as the study subject. Peripheral blood samples were collected from the patient, his parents and brother. HLA-A/C/B/DRB1/DQB1 high-resolution typing was carried out by using sequence-based typing and sequence-specific oligonucleotides. The recombination was identified by pedigree analysis. The HLA haplotype of each individual was identified by genealogical analysis. The parentage possibility was determined by short tandem repeat analysis. HLA-A/C/B/DRB1/DRB345/DQA1/DQB1/DPA1/DPB1 were determined with next-generation high-throughput sequence-based typing. The recombination sites were analyzed by family study. RESULTS: The high parentage possibilities of the family was confirmed by short tandem repeat analysis. Recombination was found between the HLA-A*24:02 A*33:03/C*14:03 in the paternally transmitted haplotype, whilst HLA-A*01:01 A*03:01/C*08:02 was found in the maternally transmitted haplotype, which had resulted in two novel HLA haplotypes in the proband. CONCLUSION: A rare case with simultaneous recombination of the paternal and maternal HLA-A/C loci has been discovered, which may facilitate further study of the mechanisms of the HLA recombination.

Genomic full-length sequence of the novel HLA-C*06:364 allele.

HLA-C*06:364 differs from HLA-C*06:02:01:01 by a non-synonymous nucleotide substitution in exon 3.

HLA-C mismatching improves outcomes following lung transplantation.

HLA (HLA) are a major barrier to transplant success, as HLA-A and -B molecules are principal ligands for T-cells, and HLA-C for Killer cell Immunoglobulin-like Receptors (KIR), directing Natural Killer (NK) cell function. HLA-C molecules are designated "C1" or "C2" ligands based on residues 77 and 80, which determine the NK cell responses. Here, we investigated donor/recipient HLA-C mismatch associations with the development of chronic lung allograft dysfunction (CLAD) following lung transplantation (LTx). 310 LTx donor/recipient pairs were Next Generation Sequenced and assessed for C1 and C2 allotypes. PIRCHE scores were used to quantify HLA mismatching between donor/recipients at amino acid level and stratify recipients into low, moderate or highly mismatched groups (n = 103-104). Associations between C ligands and freedom from CLAD was assessed with Cox regression models and survival curves. C2/C2 recipients (n = 42) had less CLAD than those with C1/C1 (n = 138) or C1/C2 genotypes (n = 130) (p < 0.05). Incidence of CLAD was lower in C2/C2 recipients receiving a mismatched C1/C1 allograft (n = 14), compared to matched (n = 8) or heterozygous (n = 20) allografts. Furthermore, ~80% of these recipients (C2/C2 recipients receiving C1/C1 transplants) remained CLAD-free for 10 years post-LTx. Recipients with higher HLA-C mismatching had less CLAD (p < 0.05) an observation not explained by linkage disequilibrium with other HLA loci. Our data implicates a role for HLA-C in CLAD development. HLA-C mismatching was not detrimental to LTx outcome, but potentially beneficial, representing a paradigm shift in assessing donor/recipient matching. This may inform better selection of donor/recipient pairs and potentially more targeted approaches to treating CLAD.

Identification of the novel HLA-C allele, HLA-C*04:520.

HLA-C*04:520, a novel HLA-C allele, differs from HLA-C*04:01:01 by one mismatch in exon 5.

Identification of the HLA-B*15:679 and HLA-C*15:02:01:61 alleles in individuals from eastern India.

HLA-B*15:679 and HLA-C*15:02:01:61 differ from HLA-B*15:12:01 and HLA-C*15:02:01:01 by a single nucleotides.

Identification of the novel HLA-C*01:02:01:74Q and -C*15:02:01:63 alleles in individuals from Madhya Pradesh.

Allele variants HLA-C*01:02:01:74Q and -C*15:02:01:63 differ from -C*01:02:01:01 and -15:02:01:01 by a single nucleotide, respectively.

Detection of the HLA-C*08:66 allele in a Taiwanese individual.

Two nucleotide substitutions in codon 152 of HLA-C*08:01:01:01 result in a novel allele HLA-C*08:66.

The novel HLA-C*07:1089 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-C*07:1089 differs from HLA-C*07:02:01:01 by one nucleotide in exon 3.

Identification of a new HLA-C allele, HLA-C*05:01:81.

At position 778 (C→T) in exon 3, the new allele C*05:01:81 is distinct from C*05:01:01.

The novel HLA-C*03:652 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-C*03:652 differs from the HLA-C*03:04:01:01 by one nucleotide in exon 3.

The novel HLA-C*14:155 allele, identified by Sanger dideoxy nucleotide sequencing in a Chinese individual.

HLA-C*14:155 differs from HLA-C*14:02:01:01 by one nucleotide in exon 1.

Discovery of the novel HLA-C*12:02:53 allele in a Taiwanese individual.

Nucleotide substitution in codon 238 of HLA-C*12:02:02:01 results in a novel allele, HLA-C*12:02:53.

Identification of five new HLA-C alleles by next-generation sequencing.

Five novel HLA-C alleles detected by next-generation sequencing: HLA-C*02:02:73, -C*03:04:106, -C*06:382, -C*07:1114Q and -C*12:408.

A novel HLA-C*03 variant, HLA-C*03:620, identified in a Chinese individual.

HLA-C*03:620 differs from the HLA-C*03:04:01:02 allele by one nucleotide substitution in the exon 3.

Characterisation of the novel HLA-C*15:274 allele using short and long-read sequencing technologies.

The novel HLA-C*15:274 allele, first described in a potential bone marrow donor from Brazil.