The Sterne family has spent much of the past 21 years wondering whatever happened to Luke. Now, thanks to genetic researchers, they have the answer.
Nicola Sterne was 33 when Luke was born in 2000, the Sterne’s second child. Nicola says she recalls feeling there was something wrong.
“He was induced. It was a horrific time.” She says an explanation from a doctor at National Women’s didn’t help. “She said, ‘He has an even chromosome translocation and we don’t know how that is going to manifest itself’.
“So, I went home with this baby and literally went through six weeks of hell.” Luke wasn’t able to feed. “He wasn’t strong enough to swallow the formula. He was shaking because he was so malnourished,” Nicola says.
Luke was sent to Starship Hospital where he was given the immediate help he needed. But as for what was actually wrong, no one knew.
Then fast-forward to 2016, and Luke was recruited into a study being carried out by Minds for Minds genetic researchers at the University of Auckland’s School of Biological Sciences and Centre for Brain Research to find the genes and genetic variations responsible for rare conditions.
“It was so important for my other children to know,” Nicola says. And two years later they did, receiving a call from their clinical geneticist. “She said, well, it’s good news. He has a syndrome – DYRK1A, a gene involved in brain development. Changes in the DRYK1A gene have been linked to intellectual disabilities, microcephaly, speech and language impairment, seizures and autism.
“It was a bit of sad day because you know there is actually something wrong,” Nicola says. But it also provided some answers and certainty for the family.
Despite not knowing what had caused Luke’s disability, Nicola and husband Richard had a third child, Kyle. “I definitely felt I was taking a risk having another child.” Her third child Kyle was not affected.
What they now know is that the genetic change in the DYRK1A gene was not inherited in Luke’s case. “It’s called a first-generation mutation. It’s random,” Nicola says.
Nicola says Luke is limited in what he can do. “He can’t shower himself. He is allowed to go to a day programme, but only for two days. He loves the Sky Tower, he loves walking – he can walk 10 kilometres easily. He had a fantastic twenty-first.”
University of Auckland researcher Dr Jessie Jacobsen leads the research project alongside Associate Professor Klaus Lehnert and Professor Russell Snell, and PhD student Chris Samson. They worked with colleagues at Massachusetts General Hospital and Harvard Medical School in Boston to resolve the complexities of the specific type of genetic rearrangement (a balanced rearrangement) observed in Luke’s DNA.
She says a balanced chromosomal rearrangement is a bit like rearranged chapters in books. “A balanced rearrangement is when you have whole chapters missing from one book (chromosome), but they reappear in another book (chromosome). As we don’t lose many of the words, just rearrange them, we often call this a balanced structural variant.”
Her research has been funded by the IHC Foundation. In the pilot project, from 2016–2018, the team conducted research with 20 families and was able to find the genes and mutations responsible for rare conditions in 14 children.
A second project, now nearly completed, had three goals. First, to provide answers for families to help manage their condition. Second, the results from these families could significantly contribute to evidence to support the use of this technology into mainstream clinical use. Third, the gathering and cataloguing of naturally occurring genetic variation in the population will allow for a more efficient approach to identify those genes that cause rare disorders.
“We are very grateful to the IHC Foundation for their help to help these families,” Jessie says.
Photo caption: The Sterne family is relieved to have some answers (from left) Patricia Alston (Luke’s grandma), Nicola, Kyle, Luke, Sophie, and Richard holding Kais.