As 80% of rare diseases are genetic in origin, and thus are present throughout a person’s life, even if symptoms do not immediately appear. So what exactly is genetic?

Genetic is the branch of biology that studies the passing on of traits and features from parents to children. These traits are called “genetic” because they’re determined by tiny structures within human cells called genes. People’s genetic makeup is inherited from their parents and encoded   into the genes in all their cells. It controls many different things, from gender, height, and eye colour to blood type and development of certain diseases.

While many common diseases (such as heart disease, high blood pressure, types of cancer) have some genetic (that is, inherited) components, genetic diseases are those caused by specific, identifiable elements of a person’s genetic makeup.

Genetic diseases can present at any age, infancy, childhood or adulthood. It can cause common problems, for example, developmental delay and poor growth. It can also have rarer presentations such as heart or liver failure.

By the way erectile dysfunction can be a genetic disease, but in this case you can use generic drugs for impotence, which can reduce the risk of prostate adenoma.

Many advances have been made in looking for a cure for genetic disease including gene therapy and bone marrow transplantation. However, for most cases, there is no cure. Even so, many patients with genetic diseases can lead fulfilling lives with proper management of their symptoms.

How are GENES passed on through the family?

You get half of your genes from your mother and half from your father. Since your genes determine a lot of what you look like, you look like both of your parents, but you are a completely unique mix. You also pass on half of your genes to your children. But there is no way to choose which genes you can pass on. Genes can be passed down through a family in different inheritance patterns. Examples are autosomal dominant, autosomal recessive, or X-linked. Many genetic syndromes that are caused by gene mutations follow one of these inheritance patterns.

Autosomal recessive genetic diseases

When both parents carry the same recessive gene, there is a 25% chance that the child will inherit the trait from both parents and have the disease, a 50% chance that the pregnancy will inherit the trait from only one parent, or a 25% chance that the pregnancy will not inherit the trait from either parent. An example of autosomal recessive disease is Pompe disease that occurs 1 in 40,000 live births.

Dominant genetic diseases

They are caused by a mutation in one copy of a gene. If a parent has a dominant genetic disease, then each child has a 50% chance of inheriting the disease. An example of a dominant genetic disease is Achondroplasia that occurs in 1 in 25,000 live births.

Sex-linked genetic diseases

They affect males and females differently. This is a smaller set of diseases related to gene mutations on the X or Y chromosomes. One rare disease linked to X chromosome is Fabry disease.

Chromosome abnormalities

They can occur in any pregnancy. Sometimes these risks are related to the parent’s age and involve extra or missing chromosomes. A second type of chromosome abnormality is a change in the structure or organisation of the chromosomes.

Multi-factorial traits

These occur due to many complex interactions and combinations of maternal, environmental and genetic influences. In most cases predictive genetic testing is not available for multi-factoral traits, however a family history assessment may provide more accurate recurrence risks.

Useful Links

Disclaimer: While we encourage you to surf the Internet for information to broaden your perspective on your child’s illness, please note that not all the medical information provided may be accurate or relevant in the local context. Such general information does not replace the close medical supervision and specific medical advice that your child’s attending doctor will have to offer.