Monthly Archives: January 2014

Doctors told us our twins were non-identical, but our DNA portraits revealed the true story

Oliver and Oscar, or is it Oscar and Oliver?

Oliver and Oscar, or is it Oscar and Oliver?

When John and Liz O’Neill were told they were going to have twins they were over the moon. During their scans they found out the twins were developing inside separate amniotic sacs, and as a result were told by the medical staff they would be non-identical.

The adorable Oscar and Oliver were born on 9th February 2012. Both parents were understandably smitten, but also amazed at how alike the tiny siblings were.

O'Neill twinsOver the next 12 months Liz and John were constantly stopped in the street or the supermarket where strangers would coo over the twins and say ‘they must be identical!’ Although they would explain no, they were actually non-identical, the twins striking similarity meant they themselves had always harboured some doubt. “I think I might have even mixed them up during bath-time once” jokes Liz.”I felt like a terrible mother because I couldn’t tell them apart!”

Shortly after the boys 1st birthday, while reading an article on twins, Liz discovered that it was actually possible for identical twins to develop in separate sacs if the egg splits very early on during development. With this new information and a sneaking suspicion that their initial instincts had always been right, Liz contacted PlayDNA to ask for help.

“I went to school with Sam, and knew through facebook that she had started a business creating DNA artwork with meaning. I thought her forensic artwork might offer some clue as to whether Ozzy and Olly were identical or not” said Liz. We agreed to help, and took samples of DNA from each family member, including the twins older brothers Jack, age 8 and Josh, age 5.

“When I saw the photos of Oliver and Oscar I too had assumed they must be identical” says Dr Sam. “I thought it would be a wonderful project to have a peek inside their genes and see what that told us about their story, and also make a wonderful family memento!”

The O'Neill family DNA Portrait

The O’Neill family DNA Portrait

Dr Sam prepared a bespoke piece of artwork for the family, which looked at ten different genes related to particular traits, such as eye colour, memory and whether you’re more likely to be an early bird or night owl. The results were pretty conclusive.

“Olly and Ozzy shared all ten genes in common – which combined with their amazing likeness is a sure sign that they are actually identical twins!” says Dr Sam. “This is made more apparent when we see their DNA portraits alongside their elder brothers, who very obviously have several differences in their DNA. We calculated the odds of them sharing these genes by coincidence, and it works out at 0.39% – in other words, less than a 1 in 200 chance. The O’Neill family now has their colourful DNA portraits framed and on the wall for all to see.

Mum Liz told us: “Thank you so much for taking the time to explain what it all means despite being so busy. We really appreciate it. It was so interesting and is all we’ve talked about since. We’ve named ourselves team night owl and are putting together our owl names and power rangers style salute! The kids are loving it. We’re so excited about having the artwork in the house and being able to explain it properly to all our family and friends. It’s a brilliant thing for the kids to be able to grow up around and learn from. I just wanted to let you know how grateful we are”.

Personalised DNA art company PlayDNA will be on Dragons’ Den on Sunday 2nd February 2014 – tune in to see how they got on!

The whole O'Neill clan!

Team Night Owl: the whole O’Neill clan!

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Filed under Customer stories, Dr Samantha Decombel, Genetics, Media

Komodo, the Magic Dragon

by Dr James Sleigh

To celebrate the appearance of PlayDNA on the BBC’s Dragons’ Den, we are diving into the mystical world of dragons…

Here be dragons

Here be dragons

Powerful, fearsome, venomous. A rare breed of predator with sharp claws, razor-like teeth, and an insatiable appetite. No, we are not talking about Deborah Meaden, Peter Jones, or even Duncan Bannatyne of Dragons’ Den fame. We are describing the Komodo dragon, the largest living lizard, and native of the Indonesian Islands of Southeast Asia. But, do they deserve their dragon moniker?

They have no wings, and they can’t breathe fire, you say. Nor do they live for centuries, or like to hoard gold.

A real dragon

A real dragon
Photo courtesy of http://ngm.nationalgeographic.com

Not a real dragon

Not a real dragon
Photo courtesy of http://hollywoodlife.com

Nevertheless, these creatures, which can grow to over three metres in length and eat up to 80% of their body weight in a single feed, do possess an almost mythical ability worthy of the dragon name.

0117_MALO_Komodo_Eggs_013A_t607Miraculously, in separate zoos in the UK (Chester and London), two female Komodos, which were completely isolated from males, laid clutches of eggs that resulted in lots of baby dragons. This ability for females to produce offspring without mating with a male is known as parthenogenesis, and is very rarely seen in vertebrate species (those with a backbone like you and me). In fact, only about 1 in 1,000 vertebrates can reproduce in this manner. It was particularly unexpected that such a large animal as the Komodo dragon would join this rather selective group.

Intriguingly, all the virgin baby dragons were males. This is because of the interesting genetics of Komodos. Much like we have X and Y sex chromosomes (XX = female and XY = male), Komodo dragons have W and Z chromosomes. However, rather than females having two of the same sex chromosome like humans, female Komodos have one W and one Z chromosome while males are ZZ. When female dragons are isolated from males, through parthenogenesis they are able to duplicate either their W or Z chromosome (along with the rest of their non-sex chromosomes), resulting in eggs that are either WW or ZZ. The WW eggs do not survive, but the ZZ eggs produce viable male baby dragons.

_66452824_komododragon

Hello mummy!
Photo courtesy of BBC

It is believed that this ability to switch between sexual and asexual reproduction has evolved as a strategy to be able to survive in the Komodo’s natural habitat of isolated islands. Females finding themselves washed up on unpopulated islands are able to reproduce asexually, producing males for future mating.

Fascinating.

Not quite cloning, but I’m sure some of the BBC dragons would be interested in making similar duplicates of themselves so they could make twice as much money! What’s that? You want to know the outcome of PlayDNA’s adventure in the dragon’s lair? Well, you will just have to wait until Sunday to see how Dr. Sam and Dr. Stuart fared…

PlayDNA is on Dragons Den Sunday 2nd February BBC2 at 9pm.

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Filed under Animals and Plants, Dr James Sleigh, Genetics, Media, Science