Man's horror as DNA test reveals he's dating his half-sister

A couple have been left devastated and horrified after a DNA test they took at Christmas revealed they are half siblings.

An unnamed man took to Reddit to share his dismay after the results from his and his girlfriend’s genetic test revealed they share the same father.

In a detailed post, he explained that the pair were both conceived by in-vitro fertilisation via sperm donors meaning the results claim they are the children of the same sperm donor.

Christmas day rolls around, and Sarah had bought the both of us 23andme DNA kits. The thing is, is that we were both conceived by in-vitro fertilisation via sperm donors,” he explained.

“Both of our fathers were infertile so our parents had no choice. Deep down, the both of us were hoping to find our biological fathers through the service.” 

The pair finally got their results and “all was well until we arrived at the “DNA relatives” section.” The results had his girlfriend’s name at the top and claimed she was his half-sister, with the pair sharing 27% of the same DNA.

The results from his and his girlfriend’s 23andMe genetic test revealed they share the same father. Photo: Reddit

He then explained how the outcome could be true, surmising that both their mothers must have been inseminated with the same man’s sample.

“What are the f**king odds, right? The fact that we’re from the same town certainly increased the odds but still.”

He told Reddit users that the news had left him and Sarah in complete shock and feeling “traumatised” at the knowledge that their year-long relationship was, in fact, “incest”.

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Claiming he turned to Reddit for a place to vent his feelings, he then said the pair were spending time apart and returning to their families to try and get more answers.

Mixed reactions

Some readers were quick to share their thoughts and revealed their sadness for the couple.

“I think you should definitely talk to a professional with this traumatising situation to help you understand that it wasn’t anyone’s fault. You simply didn’t know,” one wrote.

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“Makes you wonder if this service should continue to be provided. A company basically created a large number of half siblings in upcoming generations, which is basically incest on a large scale. Most likely women or couples chose sperm from a limited number of men,” another mused.

However, many others were doubtful about the truth of the tale.

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“My apologies if this is true but this reads like a work of fiction. Cliche lines like ‘Sarah tightly holds my hand and says ‘I hope we both find our fathers’ Contrived narrative,” one commented.

“Furthermore, don’t you have to opt into DNA relatives. Since you claimed you opened yours before Sarah, she would not have had time to opt in. Overall, this smells fake,” another added.

“I call BS on this post. The story states his GF got them the kits for Christmas. Story says “fast forward less than a month to today”, so it was supposedly this Christmas. Even if they took the tests and mailed them right away, that’s only two weeks from the date they sent in the kits to the results? When has 23andme ever been able to turn around results that quickly, at the busiest time of the year no less?” one asked.

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