Genetic background specific for TgAb discordant twins​

BACKGROUND: Epigenetic factors associated with the development of autoimmune diseases are unclear. Monozygotic twin pairs discordant for positive anti-thyroglobulin autoantibodies (TgAb) are useful to examine the epigenetic... [ view full abstract ]

BACKGROUND: Epigenetic factors associated with the development of autoimmune diseases are unclear. Monozygotic twin pairs discordant for positive anti-thyroglobulin autoantibodies (TgAb) are useful to examine the epigenetic factors because of their identical genetic background. To clarify the genetic background specific for TgAb discordant twins, we genotyped concordant and discordant twin pairs for TgAb positivity.

Subjects and Methods: 19 discordant and 185 concordant pairs for TgAb positivity were selected from the registry established by the Center for Twin Research at Osaka University. Gene polymorphisms were performed using the Omni5-4 BeadChip Kit (Illumina) to clarify genetic background.

Results: 155 polymorphisms specific for TgAb discordant pairs were significantly different in genotype frequencies from those of concordant pairs, and none of them was located on the HLA region of chromosome 6, which known as susceptible to autoimmune thyroid disease.

Conclusions: We found that the genetic background specific for TgAb discordant twins who are susceptible to epigenetic changes are different from that specific for TgAb-positive concordant twins.

(The authors are thankful to all the consultants from the Osaka Twin Research Group. This project was supported by University Grants from the Japanese Ministry of Education, Culture, Sports, Science and Technology, and by JSPS KAKENHI JP16H03261.)