GIGO

It's in the Genes

What do you call 26 assorted brothers-in-law, sisters-in-law, nieces and nephews sploshing around at a Fiji resort? A gene pool.

Sorry about that, but it was the thought that sprang to mind on our recent holiday where Peter's family got together to celebrate their mum's 70th birthday. There was a preponderance of the tall, slender Hyde ectomorphic shape, a common facial structure and a large number of turned-in little toes. It was all very intriguing, particularly to someone like me of a scientific bent and without siblings for such comparisons.

I can claim to have added my own genetic stamp to our line of the Hyde clan. Our sons, David and Perry, both have dark brown eyes, which did not come from their blue-eyed father. If you haven't encountered this basic genetics example before, brown eye coloration is dominant over blue. Put simply, this means Peter has two blue-eyed genes and so can pass only that coloration on. My eyes are brown-green, so I could have genes for just that or a mixture of brown and blue genes, the latter courtesy of my own blue-eyed father, albeit recessively invisible in me.

What this also means is that our boys' beautiful brown eyes must trace through my dark-eyed mother's line. But wait, there's more! Her father, in turn, had blue eyes, so that dominant brown comes through her mother, my grandmother. Another generation of paired female brown eyes and male blue eyes and we finally reach back to Ara and Erueti Te Ahurangi, both of whom definitely had brown eyes.

It's something I smile about every time someone exclaims over my fair, white-blond boys with their dark, dark eyes. I know where those eyes come from and how they provide a very physical link to the all-too-finely stretched connections of our Maori heritage -- those are Tainui-Maniapoto eyes.

As I write this, I am awaiting the imminent arrival of our third offspring. It will be a while before I know whether he or she has brown eyes or blue but, whatever the colour, I'll be content to see them find the world as exciting and interesting a place as I do.

Vicki Hyde is the editor of New Zealand Science Monthly.