Comments on Genetic Future: The elusive genetics of bipolar disorder

The genetics of manic-depression are elusive becau...

2009-07-03T06:38:07.786+10:00

The genetics of manic-depression are elusive because the DSM-IV diagnostic criteria encompass a wide range of different psychiatric disorders, combining elements of major depressive disorder, hypomania, and severe mania without depression.

This is similar to 40 years ago when the bulk of patients with psychiatric disease were categorized as 'schizophrenic' or 'schizoid'.

I too am slightly surprised that mapping of hype...

2008-04-08T01:03:00.000+10:00

I too am slightly surprised that mapping of hypertension has not be easier. If the variants had been driven to fixation by selection outside of Africa, this would make it pretty ideal for admixture mapping even if not for association mapping.

I'm not very sure about this but I think there might be different forms of hypertension, some of which are more strongly sensitive to salt. If so, I wonder if hypertension is a disease where better phenotyping will really help reduce the noise.

Thanks G,

I'm surprised that hypertension, ...

2008-04-07T14:38:00.000+10:00

Thanks G,

I'm surprised that hypertension, of all common diseases, has proved so difficult to find genes for. As I understand it, predisposition to hypertension is ancestral (due to salt retention being beneficial in our hot, dry African homeland) but has been selected against in populations in cooler, wetter northern climates. Because this adaptation is relatively recent, I would have guessed that some of the large-effect alleles that typically characterise early adaptation would still be segregating, i.e. there should be some reasonably common large-effect protective variants.

But in hindsight, maybe there's been enough time for them to reach fixation (assuming strong selection), leaving only the small-effect nearly neutral alleles to drift around and drive phenotypic variation in modern non-African populations.

It is also interesting to note that admixture mapp...

2008-04-07T01:42:00.000+10:00

It is also interesting to note that admixture mapping scans (Deo et al) have also failed to find much of a signal for hypertension.

Comments on Genetic Future: The elusive genetics of bipolar disorder

The genetics of manic-depression are elusive becau...

I too am slightly surprised that mapping of hype...

Thanks G,I'm surprised that hypertension, ...

It is also interesting to note that admixture mapp...

Thanks G,

I'm surprised that hypertension, ...