This observational study aims to establish a digital registry, screening platform for patients with monogenic diabetes using internet-based and mobile application technologies. The primary objectives are to:

Characterize the genetic landscape of monogenic diabetes in the Chinese population, including pathogenic variants and their distribution

Participants will:

• Enroll in the monogenic diabetes registry via mobile application or web-based platform
• Undergo molecular genetic testing to establish a definitive diagnosis

This study will include the subjects of a series of studies on monogenic diabetes conducted by our team, including neonatal diabetes, maturity-onset diabetes of the young, maternally inherited diabetes and deafness, and other monogenic diabetes caused by different causative genes, and establish a large sample database and specimen bank through follow-up and omics analysis.

Inclusion Criteria:

1. Diabetes diagnosed before 25 years of age; OR diabetes diagnosed before 35 years of age with ≥1 first-degree relative (parent, sibling, or offspring) diagnosed with diabetes before 40 years of age
2. Body mass index (BMI) at diagnosis 28 kg/m²
3. Negative glutamic acid decarboxylase antibody (GAD-Ab)

Exclusion Criteria:

1. Secondary diabetes
2. Active malignancy or history of malignant tumor within the past 5 years

Diabetes patients who completed gene test and necessary further tests and voluntary to be followed up will be included.