Have you ever wondered why you can roll your tongue but your friend can’t? Or why your little finger is crooked?
It’s all about genetics. Whilst there is a great deal of debate about nature versus nurture when it comes to personality, there can be no question that your physical attributes come from your parents. But how exactly does it work?
Genes – more correctly known as alleles – are inherited from both our mother and father. Each pair of genes provides the blueprint for our physical characteristics. But all genes are not created equal. There are essentially two types – dominant and recessive. So, if you inherit a dominant gene from one parent, and a recessive from the other, the dominant gene will appear. This is particularly apparent in eye colour – blue eye colour is recessive, so if you have blue eyes, you have two recessive genes. If you go on to have a baby with another blue-eyed person, the baby will have blue eyes. However, if you have a baby with a brown-eyed person the baby could inherit a recessive gene from your brown eyed partner, resulting in blue eyes – or the dominant brown one, resulting in brown eyes.
Then there are the polygenic genes, where more than one gene is responsible for a trait. These genes impact things like height, weight, hair and skin colour. Research suggests that Type 2 Diabetes is a polygenic trait.
So what are some dominant genes that might surprise you?
- Bent little finger – if your little finger curves inwards towards the rest of your fingers, this is dominant
- Achoo syndrome – this is a weird one! Some people sneeze when seeing a bright light after being in the dark – this is a dominant gene!
- Double Jointed-ness – a dominant gene that allows you to bend in ways other people can’t
- Tongue rolling – if you can roll your tongue up from the sides, this is the result of a dominant gene
- Coriander – if you think coriander has a soapy taste – blame it on the parents!
But let’s go back to nature versus nurture debate. There are a number of things that recent research suggests are strongly genetically linked. Some might surprise you, some might shock you, and some might provide you with a ‘get out of jail free’ card with your friends and family!
- Laziness – yes, if humans are at all like rats, extreme laziness can be genetic. Netflix please!
- Stress – how well you handle stress is at least in part genetic. Some of us should maybe look into meditation classes sooner rather than later…
- Travel – some people love it, some people hate it. Don’t fight it if those feet are itchy!
- Driving skills – don’t jump to conclusions and blame your mother! Maybe it’s your father’s fault
- Addiction – having a tendency toward addiction (chocolate doesn’t count) is actually genetic, something to watch out for if it runs in the family
- Violence – some would say this is nurture over nature, but studies suggest there is a definite genetic component to a tendency to respond violently
- Music – your taste in music is partially genetic. In my case, it came from my kids!
- Partner selection – no, it wasn’t just their beautiful eyes or the great sense of humour. You were genetically predisposed to them. Makes you look at your partner in a slightly different light, doesn’t it?
- Phobias – spiders, small spaces, heights. All genetically predisposed
One final thing you might not know about genes – around 8% of your DNA is viral. And no, this does not give you license to get a doctor’s certificate for some time off work!
At Precision Health Spine & Sports Clinic we are fascinated by all things to do with the human body. If you would like an appointment to sort out some genetic or non-genetic concerns give the clinic a call on (02) 9639 7337.