Genetic disorders are diseases that are passed down through a parent's genes. Most are rare, and usually happen to one person in several thousands or millions. They can be heredity (passed down through family) or caused by mutations in the DNA. Cancer is one of the most harmful things that can be passed down, but many other diseases can be passed down through genetics.

Within our DNA there are two kinds of traits. The first type is called recessive and the second is called dominant. Recessive traits are genes that are unlikely to happen, but do have a chance to occur. Dominant traits are the ones that are most likely to appear, and genetic disorders can exist in both.

Single-gene disorders are when a gene is mutated in the DNA to cause a disorder. There are over 4000 human diseases which happen due to single-gene defects. They can be passed on from generation to generation in multiple ways. They can however be effected by X-linked and autosomal types.

X-linked types rely completely on the chromosomal location. They are caused by mutations on the X chromosome. Since all human beings have an X chromosome, this can affect both males and females. Dominant X-linked traits are few, as most do not inherit these traits. There are a few X-linked dominant conditions that can cause the male to die rapidly, like Rett syndrome or Aicardi syndrome.

X-linked recessive disorders affect males more than females, though the chance differs based on who is giving the trait. For example, if a father has a son and has an x-linked recessive disorder they will not receive the disorder. If a mother gives birth to a daughter, they will have a 50% chance of receiving it.

Autosomal dominant traits are traits that only one affected parent is needed in reproduction. The child has a 50% chance of receiving the mutated gene, though even if a child receives the gene, they are not guaranteed to develop the disorder. One of the major diseases that can be given by this is Huntington's disease, which is a disease that causes the death of brain cells entirely.

Autosomal recessive means that both parents have a recessive trait of a single mutated gene. The two parents have a 25% chance to pass on the trait with each pregnancy. A common example of this would be cystic fibrosis, a disorder that has extremely harmful impacts on the lungs, liver, intestine, kidneys, and pancreas.

Genetic disorders are a constant issue facing our society. As we learn more about them, we can find new ways to prevent them. While some may prove to be unpreventable through natural births, one day scientists hope to have a way to genetically map all humans before they are even born. With this, we can stave off these conditions, and increase life expectancy.

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