Summary
Conditions caused by faulty genes passed through families, such as cystic fibrosis and sickle cell disease.
In depth
Examples: cystic fibrosis (recessive, CFTR gene on chromosome 7), Huntington's disease (dominant, CAG repeats), haemophilia (X-linked recessive) and sickle cell disease (recessive). Many conditions are multifactorial, caused by genes and environment together.
Screening and carrier testing help families plan.
Disorders are classified as single-gene (Mendelian), chromosomal, multifactorial (heart disease, diabetes) and mitochondrial. Newborn screening detects conditions such as PKU and congenital hypothyroidism, where early treatment prevents damage. Carrier screening can reveal risk before pregnancy, as with Tay-Sachs among Ashkenazi Jewish communities, where testing greatly reduced births.
Treatments range from diet and enzyme replacement to gene therapy; exa-cel (Casgevy), based on CRISPR editing, was approved in 2023 for sickle cell disease.
Example: haemophilia A is X-linked recessive, with factor VIII missing; Queen Victoria was a carrier and the allele spread through royal families of Europe.
Frequently asked questions
What is Inherited Disorders?
Conditions caused by faulty genes passed through families, such as cystic fibrosis and sickle cell disease.
Which area of biology covers Inherited Disorders, and how advanced is it?
Inherited Disorders is one of the 54 topics in Genetics. It is rated Beginner, so it suits learners who are starting out in biology. Related topics in this area include Sex-Linked Inheritance, Down Syndrome, Genetic Counselling.
Can you give an example of Inherited Disorders?
PKU, a recessive condition, is controlled by diet if detected at birth.
What should I learn before Inherited Disorders?
Inherited Disorders is a Beginner topic, so no earlier topic is required. Other Beginner topics in Genetics that pair well with it include Heredity, Gene, Allele.
What topics are related to Inherited Disorders?
The closest topics to Inherited Disorders are Sex-Linked Inheritance, Down Syndrome, Genetic Counselling, Homozygous and Heterozygous. Comparing them side by side is a good way to see how the ideas connect.
How can I check that I understand Inherited Disorders?
Read the summary and the in-depth section, then use the quick check on the interactive lesson for Inherited Disorders. To practise the whole of Genetics, use the Genetics quiz.
How is Inherited Disorders different from Sex-Linked Inheritance?
Inherited Disorders: Conditions caused by faulty genes passed through families, such as cystic fibrosis and sickle cell disease. Sex-Linked Inheritance: Genes on the X chromosome show different patterns in males and females, as with red-green colour blindness. Read both side by side and note what each one explains.
How should I study Inherited Disorders step by step?
First, read the summary and write the definition in your own words. Second, read the in-depth section and note any example. Third, compare it with Sex-Linked Inheritance and explain the difference aloud. Finally, take the Genetics quiz and come back to this page for any question you miss.