Sexing It Up
Red Knots are monomorphic, they show no significantly different features that would allow them to be sexed in the field. So, over the last week or so, my focus up here at Massey has been on methods to extract DNA from Red Knots and to use this DNA to determine their sex. Of importance is developing a method that allows me to extract and amplify DNA from feathers. We usually pluck only about 3-5 breast feathers and 2 scapulas from the birds. I therefore have trialled just using one feather as a DNA source and this has been hugely successful. I was able to extract DNA using a couple of methods, amplify it using PCR and primers that were specific to our lovely Knots, then run then DNA through a gel to get our results. Here's me looking all geeked up in the Farside Lab, part of the Alan Wilson Centre at Massey (I think the blue gloves will take off on the catwalk this winter).
An interesting thing about bird sex is that unlike humans, where the male is XY and the female XX, in birds the male is ZZ and the female ZW. Therefore, when doing electrophoresis the female gives two bands, at 400bp and 600bp, and the male a single band at 400bp. Here's a photo of my first gel, which shows a bit of messiness in the first column, beyond the ladder, but a clear male in the second column and some clear females out to the right. It works! Yay.