I have a genetical identical...what does this mean? Are we one and the same?
We are mono-zygotic twins: we are the result of a single egg and a single sperm which divided into two (rather awesome) individuals between day 6 and 10 after conception. From that point on, we developed as two. We were in the same environment for close to 9 months, but experienced it differently. Together. But separate.
We were Mono-chorionic, Di-amniotic (MCDC): we shared an outer sac, but had separate inner sacs (see Figure C in the image below). Our finger prints are different. Just so you know.
Our genetic map is for the most part identical - but epi-genetically, we are unique.
From the moment we became two, we developed and emerged as individuals.
Yes, we swapped name tags to trick a teacher who was not seeing us as individuals.
Yes, even now at 40, when we are together the reaction is "OMG".
I have a dozen funny stories about mistaken identity. The human brain will ignore any nuances in favour of the key features (like an inbuilt auto correct). This is why witness statements alone are not enough to convict someone of a crime....near enough is good enough for our brains.
Twins are Big Business: Long have twins been the (voluntary) guinea pigs of human research. From 'Nature Vs Nurture', study of diseases and to the epigenetic studies more recently, twins have been 'helping' researchers to understand human development and develop medical advancements (for example, these current studies).
Read an Informed Twin Birth Story The doula who tells her story knew that modern twinning was fraught with over-medicalisation. She knew her rights, her options and her responsibilities. She owned her power. And her story highlights that it is possible to have a less intensively medical birth with multiples. Back in my day....scans were not routine. My mother had to request one to confirm her suspicions: "this is either an octopus or twins". So at 6mths pregnant, a grainy scan confirmed there were two of us. I will save that story for another day.
Read a story of how a semi-paraplegic mum of twins is being supported by not-for profit Yooralla.
Have you heard of Semi-identical twins?
The Immortal Pollux, in the limerick above was a semi-identical twin to the mortal Castor. One mother, two fathers, so the greek legend goes. And when Caster died, Pollux asked that he be immortal too...and so they became the constellation gemini. Turns out, semi identical twins are not just the stuff of legends.
Do twins ever mix themselves up? I could send you straight to the paper, but it gets a mention here for winning an Ig Noble in 2017. It was a small study, but it seems if you flash an image of my twin at me, I could think it was me, and visa versa. But hey...I'm not a computer....and at least if I get lonely I can just talk to myself in the mirror and pretend it is my sister.