Anglican Mainstream

Looking at comments on the last blog about genes it is interesting to notice that someone states that the "jury is still out" on homosexuality being inborn. Yet where there is more evidence in other areas the scientific jury speaks of "mostly genetic" in the case of clinical depression. But even there we see a difference. Where identical twins are brought up together the chance of the second twin having depression if the other one is clinically depressed is 76%. Where the twins are brought up apart we see the chance drop to 67% In homosexuality we see the following statistics.

 

Where identical twins are brought up together if one twin is gay the chance of the other one being gay is 10% according to the best research (by this the scientific community means tests using twin registers rather than those recruited via the gay press). If we include bi-sexuality rather than only having exclusive feelings for the same sex the chance rises to 24 or 25% If the twins are brought up apart then the chance drops to around 3% – the same for non identical twins or just same sex siblings. This points towards a lack of biology and a higher influence of sociological and psychological factors.

 

If we compare homosexuality to schizophrenia there has been no genes found to link them with homosexual behaviour despite searches of the human genome while 4 genes have been found for schizophrenia – and even then these genes only occur in 3% of the cases.