Emmerdale's Lydia Hart (Karen Blick) was dealt a double bombshell after discovering her mum Agatha was still alive, despite her bitter long-lost sister Beth claiming she had died, and that she is at risk from a life-threatening illness that runs in her biological family.
The emotional reunion with her birth mother filled in the blanks for Lydia, born Jenny Finn, who was taken into care aged five when her mother struggled to cope with the temporary departure of her late father. After falling pregnant in her teens and burying her stillborn baby born in secret, Lydia changed her name making it hard for her real family to track her down.
Press coverage around the recent discovery of the baby's remains at Lydia's old care home led to the relatives finding each other again, and while Agatha explained she was grateful, resentful Beth's efforts to keep her estranged sibling out of their lives had not worked, she was forced to reveal a shocking truth about her father's recent death from Huntington's disease…
What is Huntington's disease?
According to the NHS website, the progressive hereditary brain disorder affects mobility and bodily functions such as communication, swallowing and breathing. It can also cause depression, mood swings and involuntary spasms, and shorten life expectancy.
Symptoms may start to occur between the ages of 30 to 50, but that can vary. It's caused by a faulty gene that results in gradual damage to parts of the brain over a period of time, and can be passed down from parents to their children – meaning there is a 50% chance Lydia could have the condition.
Although symptoms can be managed and treated to help reduce problems caused by the condition, there is currently no cure for Huntington's disease and it is usually fatal after a period of up to 20 years from diagnosis.
As Agatha explained to her daughter, there is just as much chance of her not having the disease – a genetic test can be taken to determine whether it will develop, which Beth has already had and is confirmed as being clear.
Lydia now faces the difficult decision as to whether or not to undergo the test, or if it's best not to know.
"This is a massive shock to process," says Blick. "Lydia is not sure if ignorance could be bliss. She doesn't want the Dingles to worry about her, or to be the person who makes everyone go silent when she walks into a room. Sam is always there for her – he's her rock."
The storyline continues throughout the week as Lydia tries to process the news, and decide whether she will choose to get tested.
Aussie soap Neighbours has also tackled the topic through the Brennan family, with Chloe Brennan facing her own mortality having been diagnosed with the Huntington's gene as she watches her mother Fay start to deteriorate.
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