• T2DM patients had significantly lower serum levels of cOC, ucOC, and ucOC/cOC ratio compared to healthy controls, suggesting altered osteocalcin metabolism in diabetes.
• In T2DM, cOC levels inversely correlated with HbA1c and P1NP, while positively correlated with ALP, LDL, and N-MID, indicating potential links between bone turnover and glycemic control.
• Nine SNPs in the osteocalcin gene were analyzed, providing preliminary evidence for genetic associations with osteocalcin levels and T2DM risk in the Chinese Han population.
• The study highlights the interplay between bone-derived hormones and metabolic health, offering potential biomarkers for T2DM diagnosis and management.