Heritability of thyroid peroxidase autoantibody levels in type 1 diabetes: evidence from discordant twin pairs.
Diabetologia
; 58(9): 2079-86, 2015 Sep.
Article
em En
| MEDLINE
| ID: mdl-26070305
ABSTRACT
AIMS/HYPOTHESIS:
The discordance status of (autoimmune) type 1 diabetes within monozygotic twin pairs points to the importance of environmental factors. The aim of this study was to investigate whether the environmental events causing type 1 diabetes influence thyroid autoimmunity.METHODS:
Monozygotic and dizygotic twins discordant for type 1 diabetes from the UK and USA were tested for thyroid peroxidase autoantibodies (TPOA) by radioimmunoassay. Using quantitative genetic model fitting of a liability-threshold model we estimated the contribution of genetic (heritability) and environmental factors to TPOA.RESULTS:
TPOA positivity was higher in females than in males in both cohorts and was associated with later age at diagnosis in the UK and combined cohorts (p < 0.01). TPOA did not specifically segregate with type 1 diabetes in the twin pairs (p > 0.2 in all groups). The best-fitting models showed heritability (95% CI) estimates for TPOA of 63% (37%, 80%) for the UK and 80% (51%, 92%) for US twins, while the best-fitting meta-analysis model of the two twin cohorts combined included additive genetic and unique environmental factors with a heritability estimate of 69% (50%, 82%). CONCLUSIONS/INTERPRETATION:
Risk of thyroid autoimmunity, defined by TPOA, in the context of autoimmune diabetes is, substantially, genetically determined in discordant twin pairs. Environmental factors leading to type 1 diabetes were not the same as those involved with thyroid autoimmunity. It follows that it is as important to investigate for thyroid autoimmunity in relatives of type 1 diabetes patients as it is in the patients themselves.
Texto completo:
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Base de dados:
MEDLINE
Assunto principal:
Autoanticorpos
/
Autoantígenos
/
Proteínas de Ligação ao Ferro
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Diabetes Mellitus Tipo 1
/
Iodeto Peroxidase
Idioma:
En
Ano de publicação:
2015
Tipo de documento:
Article