Lucy Hunter's tall frame is due to a genetic disorder. Yet she refused screening for her sons, who both now have the condition. She explains why she has no regrets

Two days after my son Rufus was born, I knew for sure. It was during one of those interminable cups of tea, and chit-chat about breastfeeding. My baby boy nestled in the crook of my arm. The trainee midwife craned forward to get a closer look. "Ooh," she cooed brightly. "Hasn't he got long fingers?"

At which point I burst into tears. Not so unusual for a new mum, but this wasn't straightforward baby blues. The midwife confirmed what I already instinctively knew – I had passed on the genetic disorder Marfan syndrome to my baby.

Marfan syndrome is an inherited connective tissue disorder, which sufferers have 50 per cent chance of passing on. The gene that makes the protein fibrilin, and gives skin and connective tissue its stretchy feel, is faulty. Because connective tissue is found throughout the body, Marfan syndrome can affect the skeleton, eyes, heart and blood vessels, nervous system, skin and lungs. People with Marfan's tend to be unusually tall and slender, with particularly long arms, legs and fingers. Resulting heart problems, which include aortic dissection, can be deadly. For those undiagnosed and untreated, the average age of death is 32.

The outlook is much better for those diagnosed with the syndrome: 72. Nearly seven years on from giving birth, perspective has overtaken post-natal hormones, and I realise that our family is lucky. We are diagnosed and, thus far, are relatively mildly affected. Compared to other genetic disorders, it's manageable.

It would be a mistake to see Marfan's as simply the sum of its medical parts. It affects looks as well as health. Apart from simply being gangly, those with Marfan's have less ability to store fat and muscle. I'm 5ft 11, and at 18 I weighed seven and a half stone. Strangers presumed I was anorexic. What's more, people with Marfan's tire more easily, and feel like their bodies have let them down. Seventy-five per cent of sufferers inherit it, so many have experienced a parent who is in poor health, or has died prematurely.

Marfan's cast a shadow over my childhood. My father was diagnosed in the late Sixties, and the knowledge that he was likely to die prematurely was a living grief. Perhaps unsurprisingly, he drank. He died in 1986, during an operation to replace his aortic valve. He was 52.

Throughout my twenties, I worried about passing on the gene to my children. Women with Marfan's are encouraged to have children by the age of 30. After genetic counselling, I considered the options. Although a prenatal test for Marfan's exists, the idea of aborting my own child because he is, well, like me, was absolutely abhorrent. I looked into the more palatable idea of having a "designer" embryo implanted using IVF. Then I decided to take my chances on nature.

I have never regretted my decision, despite the guilt when I realised that Rufus, and Oisín, now four, had both been affected. More immediately, super-tall children bring their challenges. Rufus has always been taller than his peers, at one point wearing clothes up to four years older than his age. As a toddler he was a real handful – controlling regular-sized two-year-olds is hard, so you can imagine what it was like in our household.

ADHD and other learning disorders are more common in those with Marfan's, and Rufus shows some of these traits. Other parents, assuming he was much older, were openly critical over what was normal two-year-old behaviour. I got into the habit of sighing, "Oh, he's so tall for two – it's a real pain." A mistake – Rufus has absorbed the message that being tall is bad, damage I am trying to undo now.

When Rufus was three, he had a developmental check. Half an hour in, I realised that the doctor thought he was seven, as she hadn't read his notes. When I picked up on this, she was clearly embarrassed, and, as he was a few months short of four, said she was looking at the milestones for four. I was surprised. Teachers are usually very precise when they refer to the age of nursery children, because a month or two makes a big difference. When the doctor sent me her report, she had recorded that Rufus was four years and nine months, and based her findings on that.

Oisín, my younger son, has not experienced the same level of criticism from others – partly because he's not as tall as Rufus, and he has the savvy of a second child. So it was upsetting to receive a visit from the health visitor, who had assured me that she was knowledgeable about Marfan's. Oisín has the typically slender physique that is a hallmark of the condition. But the health visitor was horrified and demanded to know whether I fed him. I smiled tightly, assured her I did, and prayed I wouldn't be plunged into one of those nightmare stories when social workers storm in and sweep children into care.

I can't be naive. The effects of Marfan's are going to become more marked as they progress through childhood. A news story two years ago made my blood run cold. A 13-year-old girl with Marfan's, Caroline Stillman, was bullied out of school after suffering vicious verbal abuse and physical harassment because she looked different. My father grew up in war-time Middlesbrough, a tough town for even the most robust, never mind for a red-headed, bespectacled boy with Marfan's. Strangers told him to "Eff off back to Auschwitz". By the Seventies, my sister Madeleine (who is also affected) and I had been told to Eff off back to Ethiopia.

I am constantly looking for ways to bolster my boys' self-esteem. Oisín is a natural joker, and I think he'll be able to handle the jibes. Rufus is sensitive, and has already told me he hates been different. When the time comes to explain his birthright, I hope that he'll take some comfort from the fact that although Marfan's makes you different, it doesn't stop determination, talent and even genius.

Considering its rarity, Marfan's has more than its fair share in the hall of fame – especially musically. There's the composer Sir John Tavener, Sergei Rachmaninov, Niccolò Paganini, Joey Ramone and Jonathan Larson, the writer of Rent. Others believed to have the condition include Abraham Lincoln, Tutankhamun and Mary, Queen of Scots. According to some sources, there's Osama Bin Laden, too. I might keep quiet about that one.

Marfan syndrome is an interesting disorder, not just medically. It's one that challenges our moral code. As religious leaders and politicians debate abortion on the grounds of "serious handicap", I'm wondering whether Marfan's fits this criteria. I suspect that for many people, it does. But why? Because we look different? Or has the idea of premature death become totally unacceptable to us? Passing on Marfan's is daunting, I know. But what I find more terrifying is the move towards a world where those with physical flaws and treatable illness are not allowed to be born. We may be creating a new world, but it certainly isn't a brave one.

Living with Marfan's syndrome

*About 10,000 Britons have Marfan's syndrome. It is one of the most common disorders caused by a single-gene mutation, and there is a one in two chance of parents passing it on.

*The affected gene is on chromosome 15, which is responsible for the production of fibrillin, which makes skin elastic. It is essential for eye function and found in every bone.

*People with Marfan's syndrome tend to be tall and slender, with disproportionately long limbs. The ligaments and joints are typically loose, and scoliosis can also be symptom.

*Stretch marks often occur on the skin of people with Marfan's, they bruise more easily and near-sightedness is common.

*Heart problems include leakage of the mitral or aortic heart valves, which control the flow of blood through the heart. Defects of the aortic valve can lead to serious heart failure.

*Most seriously, the aorta, can become weakened and rupture. This can be a cause of sudden death in some people with undiagnosed Marfan's syndrome. Contact sports and rigorous physical exertion is discouraged if you have the condition.

The Marfan Association UK: 01252 810 472;