Definition and Overview
All patients diagnosed with a genetic disease are strongly advised to keep their follow-up appointments with their genetics disease specialist for the proper care and management of their condition. This type of follow-up is typically conducted on a regular basis and for an extended period with the goal to continuously monitor the patients’ condition so that any problems, such as complications, can be caught and addressed at the soonest possible time.
Who Should Undergo and Expected Results
A genetics follow-up is an important part of the long-term care of patients who have any of the following types of genetic disorder:
Single gene defects – Also known as Mendelian inheritance disorders, these are very easy to pass on to an offspring and can be any one of three types:
Dominant – This abnormality can occur even when only one parent has one abnormal gene. This means that the offspring has a 50% chance of being born with it. One example is achondroplasia, which causes dwarfism.
Recessive – This abnormality is rarer because both parents have to carry the imperfect gene before it can be passed on. Even so, the baby will only have a 25% chance of being born with the disease. This is what happens with cystic fibrosis and sickle cell disease.
X-linked – This abnormality affects daughters of male carriers and sons of female carriers, hence its name. However, it is more common among males. One common example of this type of genetic disease is hemophilia.
Chromosomal abnormalities – These are caused by a variety of problems affecting a person’s chromosomes. It can come in the form of:
Aneuploidy – This occurs when there are more or fewer chromosomes than normal. Two common examples are Down syndrome, wherein the patient has three of the #21 chromosomes, and Turner syndrome, wherein there are 45 total X chromosomes.
Deletion – This means that some part of a chromosome or a DNA code is missing
Translocation – These genetic diseases are characterized by an abnormal rearrangement of a chromosomal segment
Inversion – These genetic diseases occur when a piece of a chromosome breaks, turns into an inverted position, then reattaches.
Mosaicism – These genetic diseases occur when there are two or more of the same chromosome patterns in the cells.
Teratogenic problems – These are genetic diseases caused by certain substances ingested during the foetal stage particularly during the first trimester of pregnancy. These substances are known as teratogens, and include some medications, lead, alcohol, radiation and certain types of infections.
Multifactorial problems – These are genetic diseases believed to be caused by a unique combination of factors. Heart defects, cleft palate, and spinal/neural tube defects are considered as multifactorial in nature.
The goal of a genetics follow-up is to ensure that the patient receives quality genetic disease management and treatment that is customized to his unique needs and condition, and preventative care, as needed.
A genetics follow-up appointment is also scheduled after a patient undergoes a specific treatment procedure as part of his treatment plan. The post-surgical follow-up is used to evaluate the results of the procedure or surgery. Likewise, patients will be asked to show up for a follow-up after some changes are made their treatment plan or medications.
Another type of genetics follow-up refers to the follow-up testing performed on infants with abnormal newborn screening results. The follow-up test will be used to confirm the diagnosis and obtain more information regarding the involved condition.
How the Procedure Works
Each genetics follow-up session involves the following steps:
- A review of the patient’s condition
- A physical examination
- An assessment of the patient’s symptoms
- Surveillance testing, or continuous monitoring through periodic imaging scans and other tests – The specific types of tests used depend on the nature of the genetic disease involved, but may generally include MRI and CT scans.
- An evaluation of the patient’s medications and how they are working
- An evaluation of the patient’s treatment plan and progress
Patients born with any genetic disease need to follow a long-term treatment and follow-up care plan to manage the symptoms and effects of their condition from the time they are diagnosed. Since most conditions are diagnosed at birth, most patients will need to go to follow-up visits throughout their lives.
The schedule and frequency of follow-up appointments will depend on the severity of the patient’s condition. For more serious genetic diseases causing serious symptoms or disabilities, these visits will be scheduled more frequently. For less serious cases, annual or bi-annual visits are usually sufficient.
Possible Risks and Complications
Some tests may be performed during a genetics-follow up. While most of them are proven safe for most patients (such as blood tests and buccal smears) some have some risks and limitations. For example, most imaging scans expose the patient to a certain degree of radiation. Although generally administered in safe, controlled doses, these scans may not be advisable for some individuals, such as pregnant women. Another test called pre-natal testing, which requires taking a sample of the amniotic fluid or tissue around the fetus carries a small risk of a miscarriage. These risks should be taken into consideration before undergoing any additional testing during the course of a long-term treatment plan.
- Feero WG, Zazove P, Stevens NG. Clinical genetics (genomics). In: Rakel RE, ed. Textbook of Family Medicine. 8th ed. Philadelphia, PA: Elsevier Saunders; 2011:chap 44.