Dr Melita Irving works as a consultant in clinical genetics. A paediatrician by training, she now specialises in genetic conditions, including skeletal dysplasia, fetal medicine, and genetic counselling. In this interview, Dr Irving talks to Top Doctors about her specialty, what her job entails, and how she is able to help patients.
Top Doctors (TD): Not many people have heard of clinical genetics. What is it?
Melita Irving (MI): Clinical genetics is a branch of medicine specialising in the diagnosis and management of genetic disorders. These may encompass chromosome abnormalities, rare diseases and complex genetic syndromes. Individually, these conditions are relatively uncommon, but collectively 1 in 17 people will be affected by one of these disorders. There are estimated to be up to 7,000 rare diseases. This requires a specialist doctor with the knowledge needed make a diagnosis and advise on future management. Often their relatives need help too.
TD: So what exactly does a clinical geneticist do? What kind of patients do you help?
MI: People seek the help of a clinical geneticist for all sorts of reasons. For instance, someone could be worried that their child might have a genetic syndrome because they have a number of different problems that cannot be readily explained. This might include delay in their development, short stature, an unusual appearance and birth defects. My job is to take into consideration a number of factors about the child and their family. I draw a pedigree to see if there is any important medical history in the family. Then I assess the child from pregnancy to birth and through their early childhood, looking for any clues that might point to a recognised genetic syndrome. Physical examination is required to take into consideration the physical signs. Finally, piecing all of this together, I come up with a short-list of possibilities to explain the child’s problems.
TD: Genetic testing is improving rapidly. Does that help you as a doctor in diagnosing genetic conditions?
MI: Yes, it does. In recent years basic chromosome testing has moved on from being a test where laboratory specialists look down a microscope to becoming a much more detailed, automated analysis of the way someone’s genes are arranged all together. And even gene testing has changed from being an expensive, time-consuming, often hit-and-miss exercise in diagnosis to being a simultaneous assessment of many genes relevant to the patient’s condition. This produces answers for families much faster and more cheaply than ever before, but it requires specialist knowledge to interpret complicated test results.
TD: Can you give us an example of the kind of patients and families you have helped recently?
MI: Yes. Recently the mother of a three and a half year old boy brought him to see me at The Portland Hospital’s Shard Medical Centre, as he was not yet able to walk and talk. He had a number of other unexplained medical problems too. In spite of having many tests and multiple medical opinions, no-one had taken into account all of his issues collectively, so his condition remained undiagnosed. Assessment in my clinic led to a shortlist of possible conditions and genetic testing targeted to his situation. A diagnosis was quickly reached. Now the focus is on the best management for him, such as therapies, and on genetic counselling for his extended family.
If you are interested in learning more about clinical genetics and the kind of research that Dr Irving is involved in, The Clinical Genetics Society provides further information on clinical genetics, and what to expect from a consultation with a clinical geneticist.