Tuesday, January 12, 2016

Now I Have Seen Everything!

In a recent Nature (Prostate Cancer) paper the authors state:

Digit ratio (2D:4D) has been suggested as a proxy biomarker for prenatal androgen activity and has been linked to prostate cancer, as the genes that regulate the formation and differentiation of the fingers are also related to the carcinogenesis of prostate cancer. To investigate the possible correlation between right hand, left hand and right hand minus left hand (DR−L) 2D:4D and prostate cancer of Brazilian subjects by comparing 2D:4D ratios of individuals diagnosed with prostate cancer and individuals without the disease. Also, to inquire the relationship between 2D:4D and severity of prostate cancer through Gleason scores....2D:4D seems to be a marker for screening patients for prostate cancer in an admixed population, as males with prostate cancer present lower 2D:4D than healthy subjects. On the other hand, 2D:4D does not appear to be associated with the severity of prostate cancer.

Yes, your ring finger length less your index finger length will be prognostic on PCa.  I have to try this one out with the folks at the bench! Forget the Illumina stuff, clean the tables, just use a ruler. Wait till the USPTF is told of this one, no mre PSA period! Forget the biopsies.

There is even a better one regarding this metric at Mayhew et al who relate this difference to a variety of complex physiological issues.

The Nature results states:

The PCA group presented significantly lower right and left 2D:4D (P=0.001 and P=0.002, respectively) in comparison to healthy controls, but DR−L were not significantly different between groups (P=0.589). In addition, digit ratios were not correlated to Gleason score for either hand or in DR−L.

 I think what they are saying is that if your ring fingers are much longer than your index fingers then you are less likely to be susceptible to PCa. I think. Why, no one knows. It would help to have some causation. But, hey, it is just one more test. Wait till the FDA gets this one.