When former Little Mix star Jesy Nelson announced her twins had been diagnosed with spinal muscular atrophy type 1 (SMA1), a rare genetic condition that causes muscle wastage, the news quickly made front page news.

The call for SMA to be added to newborn screening sprang to national attention and the health secretary, Wes Streeting, was quick to respond, saying Nelson was “right to challenge and criticise how long it takes to get a diagnosis”.

“I’m determined to look not just at screening for SMA, but to make much better use of genomic medicine,” he said.

But for many families affected by SMA, his intervention was bittersweet, with some saying their calls for the same kind of government action had been ignored for years.

Amy Moffatt, pictured with her five-year-old son, Oakley, says it has been a ‘painful’ journey trying to raise awareness of SMA1. Photograph: supplied

“I have been trying to raise awareness of the need for newborn screening for about four years. We’ve written many letters to Wes Streeting so it’s a bit of a kick in the teeth because he has known about it for a long time,” said Portia Thorman, head of advocacy and community at the charity SMA UK.

Her nine-year-old son, Ezra, has SMA1, ending up in intensive care as a newborn before he was diagnosed, and the struggle they faced to get timely treatment led her to pursue a role in campaigning on the issue.

“We have pretty much been ignored, especially by parliamentarians, and it feels like because it’s a rare disease and it is not impacting the masses or impacting their votes, they have just really brushed it aside,” she said.

Thorman added that Streeting was previously invited to visit a pilot study of newborn screening for SMA at the University of Oxford but declined.

Former Little Mix star Jesy Nelson’s twins have been diagnosed with spinal muscular atrophy type 1. Photograph: Ken McKay/ITV/Shutterstock

“I just think it’s a complete act of neglect that screening hasn’t been brought in by now – it’s been over six years of campaigning, more than that for some, of advocacy and talking to people and trying to get the message out there and it has been so painful,” said Amy Moffatt, whose five-year-old son, Oakley, was diagnosed with SMA1 at 10 weeks.

“For it to take Jesy and her platform to raise the awareness when people have been knocking on everyone’s doors for so long, it’s just it’s so sad.”

She had to battle to have her son’s symptoms taken seriously, before he was quickly treated with gene therapy which stopped his condition deteriorating. But he requires full-time care, including extensive physiotherapy and adaptations for his disability, which cost tens of thousands of pounds, and they have been fundraising money through the Tree of Hope platform to make ends meet.

“He is happy. He can do anything he wants to. But we’ll have to talk to our children about this one day and how different it could have been if they had been screened,” she said.

SMA, which has no cure, causes muscles to weaken and waste over time and, if not treated, it can affect mobility, as well as breathing and swallowing. Type 1 is the most severe form of the condition and without treatment, babies on average live less than two years.

England does not screen newborns for SMA, although the UK National Screening Committee has commissioned work to reassess this and Scotland has announced it will start screening in April.

Countries including the US, Germany, Japan and Ukraine have introduced screening, with about 10,000 to 14,000 babies worldwide born with SMA each year.

Oakley was diagnosed with SMA1 at 10 weeks old. Photograph: supplied

Molly Everitt, 23, who is studying for a master’s degree in medical law at the University of Liverpool and has SMA type 3, said the media narrative around the condition had been very negative, focusing too heavily downsides of the condition.

“So many of us with SMA have gone on to do really amazing things and live a very full life – having SMA doesn’t need to define your life,” she said.

She said the national spotlight on the condition had been difficult to get her head around, and she wanted to make sure the public knew people had been campaigning on this for a very long time.

“For my entire life I’ve had this condition no one has heard of, and then I went into a shop one day and SMA was on the front page of the newspaper. It’s just the most surreal feeling,” she said. “We have been campaigning for years but no one has been listening, and it’s taken someone famous to speak out and suddenly everyone is.”

Charlie Mosey and four-year-old Rupert. Photograph: Supplied

“It’s quite bittersweet,” said Charlie Mosey, mother to four-year-old Rupert, who has SMA1. “It’s fantastic Jesy has helped to raise the profile and get the news talking about it. But I think it’s a shame that it’s taken a celebrity to get it into the media.”

The family has raised more than £500,000 for clinical trials on SMA since Rupert’s birth, who was one of the first infants in the country to receive gene therapy for SMA.

“We’re very close with a lot of the clinicians who have been campaigning for clinical trials for newborn screening for years and it just keeps getting pushback. But had Rupert** **been tested at birth, he would have such a different prognosis,” Mosey said.

A Department of Health and Social Care spokesperson said: “We are grateful to all those who have campaigned tirelessly on this issue, including SMA UK and the many families who have shared their experiences over the years. We have heard their concerns and understand their frustration.

“The UK National Screening Committee has recommended a large-scale study into newborn screening, and a call for research is now live. As part of a trial in the NHS, hundreds of thousands of babies will be screened for SMA. We will continue to work closely with charities, clinicians and families as this work progresses.”