The HKCH Clinical Genetics Service Unit (CGSU) is the first such unit in the Hospital Authority. The team consists of specialists in Genetics and Genomics (Paediatrics), nurses, genetic counsellors and bioinformaticians. Serving patients with suspected or confirmed genetic diseases, it provides one-stop care including assessment, investigation, diagnosis, treatment, counselling and prevention.

Dr Luk Ho-ming, consultant in-charge of CGSU stated that unlike other HKCH clinical departments, they serve patients of all ages, "Any patient or family suspected or confirmed to have genetic diseases are potentially our clients. Our clinic mostly provides consultation for children who are referred by paediatricians, worrying that they may have genetic syndrome. There are also pregnant women with abnormal prenatal exam results or related family history. Some adults have very unique symptoms or abnormally early age of onset. They should also be considered for referral to us for assessment."

Family-based genetic counselling

Genetic counselling is one of the key services of CGSU. During the first appointment, the doctor will ask patients about their medical and family history and perform physical examinations. A family tree will be drawn for pedigree analysis. After assessment, if the patients are suspected to have genetic disease, the doctor will advise them to undergo appropriate genetic tests. Dr Luk said, "The genetic report is not just a simple positive or negative. We have to explain its meanings to the patients thoroughly, such as the disease-causing gene, potential symptoms and complications, mode of inheritance, means of prevention, and reproductive risk. If needed, we would refer the patients to other specialties for follow-up. We serve and counsel the whole family, not just individual patients. If there is concern that the problem may affect other family members, we would invite them all to come for assessment and genetic counselling."

▲Educational leaflets and videos are produced to enhance public understanding of clinical genetics services. They also prepare patients for their upcoming consultation and genetic tests.

Ending the diagnostic odyssey

"Some patients spend their entire life looking for the cause of their disease, but to no avail. Even though many genetic diseases have no cure now, if we are able to make a diagnosis, it still means a lot to them by putting an end to the odyssey, and could assist their clinical management and family planning," Dr Luk said. He shared that a couple had given birth to two children with the same uncommon disease. Subsequent test identified a genetic mutation in both. When the parents decided to have their third child, they underwent in vitro fertilization and were able to select a normal embryo to increase the chance of carrying a healthy baby.

▲Dr Luk Ho-ming, consultant in-charge of the Clinical Genetics Service Unit remarks that some patients have been seeking for answers for years. Through the team's help in reaching a diagnosis, patients and their families could find psychological relief. It also facilitates subsequent disease management and prevention.

Multi-disciplinary management for the best results

CGSU had set up cross-specialty clinics in collaboration with dermatology, ophthalmology, endocrinology, orthopaedics and neurology etc. Dr Luk remarked, "No single doctor knows all the diseases in the world. Patients with complex genetic conditions require joint management by different specialties."

▲The CGSU handles genetic diseases that are rare and unique. Regular meetings are held to discuss how to tackle cases.

The establishment of CGSU has created two new positions, namely genetic counsellor and bioinformatician.

Bioinformatician: the data interpreter

How to look for clues from the galaxy of raw genetic data? Bioinformatician Yiu Wing-chung revealed, "We select appropriate bioinformatics tools and database to collate and analyze the data generated in the lab. Our interpretation can facilitate doctors in making diagnosis. We also need to maintain massive data effectively, so that useful information can be promptly retrieved as a basis for clinical decisions."

A bioinformatician needs to think like a detective. Said Yiu, "Previously in our database, there was a genetic mutation repeatedly classified as 'uncertain significance'. One doctor noticed that all entries actually came from the same family, and asked us to look into it. Eventually, we successfully re-classified it as a disease-causing mutation, which enabled doctors to make suitable treatment plan."

Though Yiu spends most time with the computer, he feels great responsibility through taking part in the diagnosis and treatment process, "Every decision may influence the disease management of patients and their quality of life."

▲After graduating from biochemistry, Yiu Wing-chung pursued further studies in genomics and bioinformatics, as well as medical laboratory science. He wishes to apply his professional skills in clinical setting.

Genetic counsellor: not just chatting

A genetic counsellor's role starts at obtaining patients' consent to undergo genetic testing, and a new case often takes more than an hour. Genetic counsellor Phoebe Wu said, "We inform patients the purpose and limitation of the test, and answer all queries they have. Some people worry the findings will affect their insurance, job and education prospect." After the test, she will explain the report in detail, including whether a problem is found, impact on family members, and management plan. Phoebe admitted her job is challenging, "There are diseases which I have never heard of. I have to study hard before meeting my patients."

For many families, the psychological pressure is greater than physical pain. Phoebe once counselled a mother who came with a child with developmental delay and intellectual problem. "She cried the whole time, fearing that her dietary choices during pregnancy had affected her child. After counselling, she finally decided to have her child undergo medical tests. As she left, she thanked me for listening to her story. This case made me realize that this job requires not only expertise, but also empathy and counselling skills to manage the emotional needs of patients and their families."

▲Once a nurse, Phoebe Wu obtained a master's degree in medical genetics and became a genetic counsellor. Through public education, she hopes to eliminate discrimination towards patients with genetic diseases.

Partnering centre of Hong Kong Genome Project

The government launched the Hong Kong Genome Project (HKGP) in 2021. It covers cases with undiagnosed diseases, hereditary cancers, and those related to precision health, aiming to benefit patients with more precise diagnoses and personalized treatment. At the same time, the data collected will be used to build a genome database of the local population to facilitate the clinical application of genomic medicine and scientific research.

The HKCH is one of the partnering centres of HKGP to recruit suitable patients for receiving whole genome sequencing on a voluntary basis. Dr Luk Ho-ming said, "Regular clinical tests have their own limitations. However, whole genomic sequencing will not be the first choice because it is very complex and time consuming. We target to invite suitable patients and their families to join this research project, hoping to give them an answer."

More than 2,000 families have been recruited through HKCH so far. Some have already received their reports, and a proportion of them have successfully identified the cause of their diseases. The hospital will continue to refer eligible patients to the project in the next few years.

▲HKCH team members who are involved in the Hong Kong Genome Project.

Uncommon disorders database

In 2021-22, HKCH has begun to develop a database for individual uncommon disorders in phases to facilitate healthcare service planning and provide reference for diagnosis and treatment.

The data is derived from existing records in the HA clinical information system, which is then verified and analysed by healthcare professionals. The database lists the total patient number, age group, gender, and alive / death status of each disease.

At present, the database covers 25 metabolic diseases, four neurological diseases and one endocrine disease, for example, classic phenylketonuria, congenital adrenal hyperplasia, spinal muscular atrophy and tuberous sclerosis complex. More diseases would be added into the database in the future.