Healthdirect Free Australian health advice you can count on.

Medical problem? Call 1800 022 222. If you need urgent medical help, call triple zero immediately

healthdirect Australia is a free service where you can talk to a nurse or doctor who can help you know what to do.

DNA structure

DNA structure
beginning of content

Guide to genetic disorders

5-minute read

Genes are one of the basic units of life. Problems with genes can cause health or development problems. Some genetic disorders affect people from birth, others develop later in life. If you are concerned that you or someone you care for has, or might have, a genetic disorder, this page will provide you with more information.

Where are genes made of?

Almost every cell in your body has a centre called a nucleus. In almost every nucleus, there are 46 chromosomes. Chromosomes are passed from parent to child, and are the vehicle for carrying all that you inherit from your parents.

Chromosomes are made of a chemical compound called DNA (deoxyribose nucleic acid). A gene is a small section of that DNA. You have more than 20,000 genes in you.

How do genes influence your life?

Genes contain the recipes for who you are, and they influence your life from the moment you are conceived. They have a strong influence over how you look and the colour of your eyes, hair and skin.

But genes don't switch off the moment you're born. They also play a part in your personality and how you think about the world. They continue to influence your health and wellbeing for as long as you live.

They do this by instructing the body to produce the proteins that are used by cells. These proteins will help you to do things such as grow, digest food and think. Some will help protect you against cancer, while others will allow cancer to grow.

The way your genes work can be influenced by many different things, such as your way of life or the environment around you. This field of knowledge is known as epigenetics.

What's a genetic disorder?

A genetic disorder is a health condition that comes about because of a problem with a gene or with a chromosome.

A problem with a single gene is known as a gene mutation. You can have a gene mutation without it causing any problems. But some gene mutations can cause problems, for example cystic fibrosis, Huntington's disease and haemophilia

If you have a problem with a chromosome, that will probably cause noticeable problems. Some people have a missing chromosome, some have an extra chromosome, some have a broken chromosome. Down syndrome, Turner syndrome and Klinefelter syndrome are all examples of chromosomal disorders.

Why do genetic disorders occur?

Most genetic disorders occur by chance. Genes and chromosomes are complex, and they often get changed slightly in the formation of new life.

Some disorders are passed down from a parent. If a parent has a damaged gene or chromosome, and that is passed down to a child, the child's health might be affected.

Still others come about through changes in a person's DNA during their life. For example, radiation from the sun can damage a person's DNA in a way that it allows skin cancer to develop.

Are genetic disorders always inherited?

Many genetic disorders are inherited, but many others are not. Some occur simply because a piece of genetic material was damaged as it was being passed from parent to child. In that case, a child can have a genetic disorder that the parent does not have. The damage to the gene is known as a spontaneous mutation.

Do they always show up in babies?

No. Some genetic conditions can be seen from birth. Others show up during childhood, adolescence or adult life.

What about testing for genetic disorders?

Some genetic disorders can be tested for. There are many issues to consider before having genetic testing, such as the effect of a test on other family members or whether having a test might affect your working conditions or your chances of getting insurance. You should not have genetic testing without thinking it through carefully.

If you want to discuss testing, it is worth starting with your family doctor or a genetic counsellor. A genetic counsellor is an expert in working with families to discuss genetic conditions. They can talk to you about whether testing is available, the benefits and risks of testing, about privacy and confidentiality, about work and insurance, and about talking to members of your family. They generally work with other experts in genetics.

Some testing is available online or without the involvement of a health professional. The National Health and Medical Research Council warns that people should be cautious of this

Learn more about genetic testing.

Where to go for help?

If you want to try to prevent genetic disorders that run in your family, or if you want to try to detect any possible genetic conditions, it is best to talk to either your doctor or a genetic counsellor. To find a genetic counsellor, go to the Australian Society for Genetic Counsellors.

If you have a genetic condition in your family, there are many support groups you can join. Some meet in person while others operate online or by telephone. You can find some listed by the Human Genetics Society of Australia, and you can find others by searching for the condition you are concerned with.

More information

The NSW Centre for Genetics Education is a good source of more detailed information on genetic disorders and services.

If you're pregnant or thinking about having a child, see Pregnancy, Birth and Baby's information on genetic counselling or call the helpline on 1800 882 436.

If you or someone you care for has a rare genetic condition, you may be able to find a support group through Genetic Alliance Australia.

Last reviewed: July 2018

Need more information?

These trusted information partners have more on this topic.

Top results

Genetic conditions

A genetic condition occurs when you inherit an altered (changed) gene from your parents that increases your risk of developing that particular condition. However not all genetic conditions are passed down from your parents, some gene changes occur randomly before you are born.

Read more on WA Health website

Genetic conditions | Cerebral Palsy Alliance

Thousands of Australians have genetic conditions that cause physical or intellectual disabilities. Some of these conditions are inherited, while others are caused by random alteration in one or more genes in the persons body.

Read more on Cerebral Palsy Alliance website

RANZCOG WEBSITE - Prenatal Screening for Chromosomal and Genetic Conditions

The principle of screening is to offer a safe, accessible test to identifywomen with an increased chance of having a baby affected by achromosomal or genetic condition

Read more on RANZCOG - Royal Australian and New Zealand College of Obstetricians and Gynaecologists website

Genetic testing for hereditary diseases information | myVMC

Genetic testing involves analysing a person's DNA. It can be used to assess their risk of hereditary (genetic) conditions such as cystic fibrosis.

Read more on myVMC – Virtual Medical Centre website

Genetic testing for disability in children | Raising Children Network

Genetic testing looks for gene abnormalities. If theres the chance of a genetic condition in your family, doctors might recommend genetic testing.

Read more on Raising Children Network website

Genetic counselling for disability | Raising Children Network

If your child is diagnosed with a disability or genetic condition, your doctor might suggest genetic counselling. Read how genetic counselling can help you.

Read more on Raising Children Network website

Klinefelters syndrome, a chromosomal condition affecting males | Andrology Australia

Klinefelters Syndrome is a genetic condition that only affects males. The condition is present from birth and is due to an extra X chromosome.

Read more on Andrology Australia website

Porokeratosis - South East Skin Clinic

Porokeratosis, or DSAP, is a genetic condition that causes discrete patches on the arms and legs.

Read more on Skin Check website

Diagnostic tests for your baby during pregnancy

A diagnostic test is used to confirm a chromosomal condition, such as Down syndrome, or a genetic condition in the baby.

Read more on WA Health website

Fabry disease - ACD

Fabry disease is a rare genetic condition, belonging to a group of diseases called lysosomal storage disease

Read more on Australasian College of Dermatologists website

Healthdirect 24hr 7 days a week hotline

24 hour health advice you can count on

1800 022 222

Government Accredited with over 140 information partners

We are a government-funded service, providing quality, approved health information and advice

Australian Government, health department logo ACT Government logo New South Wales government, health department logo Northen Territory Government logo Government of South Australia, health department logo Tasmanian government logo Government of Western Australia, health department logo