{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T04:55:51Z","timestamp":1776142551826,"version":"3.50.1"},"reference-count":21,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2026,4,14]],"date-time":"2026-04-14T00:00:00Z","timestamp":1776124800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Endocrinol."],"abstract":"<jats:sec>\n                    <jats:title>Background<\/jats:title>\n                    <jats:p>Hemoglobin A1c (HbA1c) is a critical biomarker used for the diagnosis and management of diabetes. However, nonglycemic genetic variations may affect the accuracy of HbA1c measurements.<\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Methods<\/jats:title>\n                    <jats:p>\n                      We presented a clinical evaluation of a type 2 diabetic patient with an\n                      <jats:italic>SLC4A1<\/jats:italic>\n                      (solute carrier family 4 member 1) gene mutation, characterized by high blood glucose and low HbA1c, and estimated the carrier frequency of\n                      <jats:italic>SLC4A1<\/jats:italic>\n                      variants in Chinese population.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Results<\/jats:title>\n                    <jats:p>\n                      A 56-year-old patient with type 2 diabetes presented with a low HbA1c level, an elevated glycated albumin percentage (GA), normal hemoglobin and albumin levels, hemolysis, and increased red blood cell osmotic fragility. Exome sequencing revealed a heterozygous mutation in\n                      <jats:italic>SLC4A1<\/jats:italic>\n                      gene (c.1239_1241del), which is associated with hereditary spherocytosis. Further research indicates that around 0.756% of individuals in China carry pathogenic or likely pathogenic\n                      <jats:italic>SLC4A1<\/jats:italic>\n                      variants.\n                    <\/jats:p>\n                  <\/jats:sec>\n                  <jats:sec>\n                    <jats:title>Conclusions<\/jats:title>\n                    <jats:p>\n                      We report the\n                      <jats:italic>SLC4A1<\/jats:italic>\n                      c.1239_1241del variant, which perturbs HbA1c via nonglycemic mechanisms, likely through a reduction in the erythrocyte lifespan, and similar variants may not be rare in Chinese population.\n                    <\/jats:p>\n                  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