06 June 2026
: Case report 
Hyperglycemia Due to HNF1A-Mutation-Associated Maturity-Onset Diabetes of the Young (MODY) in a 6-Year-Old Kazakh Girl
Challenging differential diagnosis, Diagnostic / therapeutic accidents, Rare disease
Aiganym B. Toleuzhanova ABCDEF 1*, Elena Zholdybayeva ABCDE 1, Sholpan Eslamgalieva BD 2, Gulnara Svyatova BC 2, Ainash Akhmetollayeva BCD 3DOI: 10.12659/AJCR.951678
Am J Case Rep 2026; 27:e951678
Table 1 Characteristics of selected maturity-onset diabetes of the young variants.
| Gene/subtype | Mutation type | Variant type | GNOMAD_EXOMES_AF | HGVS.c | HGVS.p | Putative impact | P3_1000G_AF | CLINVAR_CLNSIG |
|---|---|---|---|---|---|---|---|---|
| HNF1A/MODY3 | Missense | SNP | 0.354886 | c.79A>C | p.Ile27Leu | Moderate | 0.298522 | Conflicting classifications of pathogenicity |
| HNF1A/MODY3 | Frameshift | Deletion | – | c.183delC | p.Asn62fs | High | – | – |
| HNF1A/MODY3 | Missense | SNP | 0.337437 | c.1460G>A | p.Ser487Asn | Moderate | 0.317692 | Benign |
| HNF1A/MODY3 | Missense | SNP | 0.996461 | c.1720A>G | p.Ser574Gly | Moderate | 0.985224 | Benign |
| NEUROD1/MODY6 | Missense | SNP | 0.70222 | c.133A>G | p.Thr45Ala | Moderate | 0.770767 | Benign |
| KLF11/MODY7 | Missense | SNP | 0.0925768 | c.185A>G | p.Gln62Arg | Moderate | 0.0579073 | Conflicting classifications of pathogenicity |
| CEL/ MODY8 | Missense | SNP | 0.282687 | c.1226C>T | p.Thr409Ile | Moderate | – | Benign |
| PAX4/MODY9 | Missense | SNP | 0.734767 | c.986A>C | p.His329Pro | Moderate | 0.670527 | Conflicting classifications of pathogenicity |
| PAX4/MODY9 | Missense | SNP | 0.00284742 | c.598C>A | p.Arg200Ser | Moderate | 0.00459265 | Benign/Likely benign |
| ABCC8/MODY12 | Missense | SNP | 0.635544 | c.4171G>T | p.Ala1391Ser | Moderate | 0.726438 | Benign |
| KCNJ11/MODY13 | Missense | SNP | 0.638307 | c.1009G>A | p.Val337Ile | Moderate | 0.730631 | Benign/Likely benign |
| KCNJ11/MODY13 | Missense | SNP | 0.640198 | c.67A>G | p.Lys23Glu | Moderate | 0.737021 | Benign/Likely benign |
| Variant annotation, population allele frequency data (gnomAD, 1000 Genomes, ESP6500), clinical interpretation (ClinVar), and in silico prediction scores were obtained from the official bioinformatics annotation report provided by MacroGen (Seoul, Republic of Korea). GNOMAD_EXOMES_AF indicates the alternative allele frequency in the gnomAD exome dataset. HGVS.c describes the variant at the DNA level using Human Genome Variation Society nomenclature, and HGVS.p describes the corresponding protein-level change. Putative Impact represents a simplified estimation of variant impact or deleteriousness (High, Moderate, Low, Modifier) P3_1000G_AF indicates the nonreference allele frequency in the 1000 Genomes database. SNP – single nucleotide polymorphism. | ||||||||