The Role of Cell Growth-Related Gene Copy Number Variation in Autoimmune Thyroid Disease

Autoimmune thyroid disease (AITD) is a recurrent and refractory clinical endocrine disease. Some studies have shown that the incidence of AITD is not only related to iodine, a kind of environmental factor, but that susceptibility genes also play a crucial role in its pathogenesis. Since research on susceptibility genes is still underway, the aims of this study were to assess the association between copy number variations (CNVs) and AITD, to identify genes related to susceptibility to AITD, and to explore the risk factors in the occurrence of AITD. Blood samples from five AITD patients and five controls from each area were assessed by chromosome microarray to identify candidate genes. The copy number (CN) of the candidate genes and urinary iodine levels were determined in adults, including 158 AITD patients and 181 controls, from areas having different iodine statuses. The cell growth-related genes, glypican 5 (GPC5), B9 domain containing 2 (B9D2), and ankyrin repeat and suppressor of cytokine signaling [SOCS] box-containing protein family 11 (ASB11), were selected as the candidate genes. The distribution of GPC5, B9D2, and ASB11 CNVs in AITD patients and controls was significantly different, and high urinary iodine levels and GPC5 CNVs are risk factors for AITD. There was no significant association between urinary iodine level and CNVs of the candidate genes. High urinary iodine levels and GPC5 CNVs are risk factors for AITD, but an association with the occurrence of AITD was not found.