Genetics frequently asked questions

Who will I see?

You will be seen by a member of the medical genetics team. This may be a doctor who specialises in genetics or a genetic counsellor.

How long is the appointment?

Most genetic appointments are 45 to 60 minutes long, so you should not feel rushed. Several relatives may attend the appointment together if they wish. Follow up appointments may be organised at one of our specialist clinics. This may take longer as you may be seen by several medical specialists with expertise in different aspects of the genetic problem in your family.

What will happen at my appointment?

The details of your appointment will vary depending on the reason for your referral but will often include:

  • Assessment of the problem that has brought you to the clinic which will be discussed in detail. The doctor or counsellor will ascertain what questions you may have and what you would like to get from your visit.

  • A family tree will be drawn which may include medical details of relatives, such as cause and age of their diagnoses or death. It is useful to have found out these details before you come to the clinic or bring a relative that may know.

  • A medical examination may be carried out on relevant members of the family.

  • The doctor or counsellor will explain the genetic issues to you and discuss all available options

  • You will be encouraged to ask questions and to make your own decisions about what to do with your genetic information. The doctor or counsellor can help you with this, but will not make decisions for you.

In some situations, tests (such as blood tests) may be offered. Sometimes you will be able to provide a sample on the day. At other times you will be asked to take some time to come to a decision about whether to proceed with a test and offered the opportunity to come back at a later date.

At the end of the appointment a plan will be made. This may include information gathering, special tests and/or another appointment.

What is a genetic test?

Genetic information is stored in the form of genes in every cell of our body. Genes are a form of code, comparable to recipes, which tell our bodies how to develop and function. We have about 30,000 genes that control our development and health. Slight differences in the code of these genes are responsible for most of the differences between individuals. If there is a serious mistake in the code of one or more of these genes or if they are missing or duplicated then we may be born with, or develop, a genetic disorder. The type and severity of the disorder will depend on which gene is faulty.

Each of us has two copies of most genes, one inherited from our mother in the egg cell, the other from our father in the sperm cell. This is why we inherit traits from our parents, including those that cause medical conditions. Current technology allows us to examine genes in individual people to look for changes in the code and to see how these are inherited within a family. Looking for a particular gene change that may be responsible for a medical condition in a family is called a genetic test. Because genetic information is stored in all cells of the body, a genetic test can be performed on a small blood sample or on other tissues such as skin cells.

Genes are packed together into 23 pairs of chromosomes, each containing several thousand genes. Sometimes, an entire chromosome or part of a chromosome may be lost or duplicated or broken. Down syndrome, where there is an extra copy of chromosome 21, is one example of this. Specific genetic tests can also detect these changes in an unborn baby or in an individual where chromosomal changes are suspected.

A genetic test may be offered:

  • To correctly diagnose a disorder in a patient who has features/symptoms – this is termed ‘Diagnostic testing’. This in turn can help to inform decisions on treatment, surveillance and risks to other members of the family.

  • To determine whether an asymptomatic individual is at risk of developing a disorder later in life - this is termed ‘Predictive testing’ (see below).

  • To find out if an unborn baby is likely to be born with or develop a serious or life/threatening condition – this is termed ‘Prenatal diagnosis’.

What is a predictive test?

This is a test performed on a sample from a healthy individual to find out whether they have inherited a gene fault that may eventually cause symptoms of a disorder. Examples of this include Huntington disease, myotonic dystrophy and some of the familial cancers.
Predictive tests are only offered to people who are known to be at risk of a genetic disorder because of their family history. The test can only be done when the nature of the genetic change is known.

Because it is a difficult and sometimes life-changing decision for a healthy and symptom-free person to have a predictive test, it is only offered after genetic counselling and when sufficient time has elapsed for an individual to think carefully about all of the implications for themselves and their relatives.

Individuals wanting more information about predictive testing should contact their GP for a referral to see a member of the medical genetics team.

What will happen after my appointment in the genetics clinic?

We will write to the referring doctor (your specialist or GP) with a summary of the consultation and the advice given and any plans which have been made (eg. for further investigation or follow up). You will usually be sent a letter summarising what was discussed at the appointment and what plans were made. If anything is unclear, you should contact the doctor or counsellor whom you saw in clinic.

 

Confidentiality:

Patient files in Medical Genetics are kept separate from your general hospital notes.