We are still working hard on analysing the data that we have collected since 1989 and a clutch of new manuscripts have been accepted for publication in scientific journals.
Recently (Diabetologia 2015, in press,http://dx.doi.org/10.1007/s00125-015-3517-8) we found that higher levels of some amino acids, in particular tyrosine, were already present in non-diabetic South Asian individuals back in 1989-91. Some of these amino acids, again especially tyrosine, more strongly predicted later development of type 2 diabetes in the South Asian people than in the Europeans in our study, even after adjustment for other risk factors such as obesity and insulin resistance. A given increase (one standard deviation) in tyrosine increased risk of developing diabetes by just 10% in Europeans, while in South Asians the increase in risk was 47%.
This study has fitted another piece of the jigsaw of complicated underlying reasons as to why South Asians are at such high risk of developing type 2 diabetes compared with European origin populations. This is the first study that has looked at the links between amino acid levels (the building blocks of proteins) and the future development of diabetes in people of both European and South Asian origins living in one geographical area. Disturbances of amino acid are likely to occur in the liver, kidneys, muscle and adipose tissues. We don’t pretend to have all the answers, but believe that our findings suggest that amino acid disturbances (in particular tyrosine) may be a focus for future research, paving the way for better prevention and potentially for targeted treatments in South Asian individuals.
In another recent manuscript (Psychological Medicine, 2015, http://www.ncbi.nlm.nih.gov/pubmed/25677948) we found that people of South Asian, African or African–Caribbean origins were significantly more likely to have depressive symptoms than people of European origin. These symptoms were most explained (but not entirely) by physical health in the South Asians and by socioeconomic disadvantage in the African and African-Caribbean groups. The study highlights the need to build on understanding for these ethnic differences and to identify opportunities for interventions to address inequalities.