A St Albans family whose young baby underwent life-saving gene therapy treatment costing £1.8m are calling for early screening for rare conditions to ensure other parents have the same opportunity they did.

George and Charlie Mosey's son Rupert was diagnosed with spinal muscular atrophy (SMA) when he was just eight weeks old and given a life expectancy of only seven months.

Charlie explained: "When other babies were beginning to lift their heads and spend time on their tummy, Rupert would just face-plant the floor and cry. He was unable to move his legs, his arms were becoming weaker every day, and he stopped moving his head."

When their GP suggested this was because he had delayed reflux they asked to speak to a specialist, but were told to give him more time as he was also colicky.

They eventually saw a London neurologist who assessed Rupert, and for the first time the family heard about the condition SMA, a degenerative, genetic neuromuscular condition that causes muscle weakness and wasting due to the loss of motor neurons.

Charlie explained: "Many doctors are not aware of the disease and its symptoms, which delays diagnosis. Every day is crucial, especially for babies with SMA type 1, the most serious type of the condition - motor neurons die every minute."

That evening, in desperation, George and Charlie took Rupert to Watford General Hospital, and with the help of a senior paediatric consultant, Rupert's bloods were sent to Great Ormond Street Hospital to test for SMA, and a few days later their worst fears became reality.

But despite his devastating diagnosis, luck was on Rupert's side and he became the second baby in England to receive a one-time infusion of the world's most expensive drug - Zolegensma - when he was just 11 weeks old.

Herts Advertiser: Little Rupert Mosey was diagnosed with spinal muscular atrophy at just eight weeks old.Little Rupert Mosey was diagnosed with spinal muscular atrophy at just eight weeks old. (Image: Mosey family)

Zolgensma uses harmless, genetically engineered viruses to deliver functioning SMN1 genes, in order to increase SMN protein levels. Once the virus is introduced into a person, it is able to travel around the body and get to a variety of different cells to help restore some of the SMN protein that is missing in SMA.

He is now 11 months old and thriving thanks to this treatment, which undoubtedly saved his life. Since being infused with Zolgensma, and with the help of daily physio by his mum, Rupert can now control his head, move his arms with brilliant hand dexterity, sit unassisted for three minutes and is learning to stand, supported by orthotic braces.

The Moseys said they will be eternally grateful to the NHS for saving Rupert's life, and are now campaigning to increase awareness of spinal muscular atrophy and raise funds for the charity SMA UK, Great Ormond Street Hospital and a charity in Italy who all supported them and helped Rupert during those crucial few months.

Charlie is now involved in a policy project about the importance of in utero and newborn screening for rare conditions such as SMA.

She said: "Fiinding out your child has a rare genetic condition turns your world upside down. But if you know what you have, you know what to expect.

"Even if you knew from before and there is no treatment available, at least you know how to deal with it and how to make their life more comfortable."

She also wants to raise awareness of the symptoms and increase doctor training, and investigate how the journey that families go through could be improved.

Before 2007, without intervention for breathing difficulties, and long before any treatment was available, the life expectancy of a child with SMA Type 1 was less than two years. Today, about one in 10,000 children are born with SMA (in the UK approximately 45 children are born with SMA Type 1 each year).

You can follow Rupert's journey on Instagram - @rallyroundrupert and donate to his parents' chosen charities (SMA UK, GOSH, and Sapre Italy) by clicking on https://gofund.me/7b242b8c