Genetic Mutation

Genetic Mutation

In this day and age genetic mutation is something we often hear about, with the main contributions being down syndrome which is also known as trisomy 21 and autism. Genetic mutation is a permanent alteration in the DNA sequence that makes a gene. A mutation of these sorts are linked to genetics. Down syndrome is the result of a chromosomal abnormality. However, autism is fairly new in the genetic mutation world as researchers have just recently connected autism to genetics.

Down syndrome occurs in every one in 1,000 births. There are three types on down syndrome which include nondisjunction, translocation and mosaicism. Standard trisomy also known as nondisjunction is when the extra chromosome comes from either the egg or sperm cell. Roughly 90-95% of all down syndrome is trisomy 21. Translocation is caused when a piece of chromosome 21 is located in another chromosome such as chromosome 14. Translocation occurs in about 3-5% of down syndrome cases. Mosaicism is when a person has mixed cells, some which contain 46 chromosomes and some containing 47 chromosomes. Mosaicism occurs in about 2-5% of down syndrome cases. The physical effects of down syndrome differ also however, most people with down syndrome have very distinct characteristics. An upward slant to the eyes, low muscle tone and a small stature; each can differ in degree with each person.

A recent study determined that autism is also a genetic mutation disorder. In individuals with

autism, duplication of the 15q chromosome is referred to as Dup15q syndrome, which is one of the most common genetic abnormalities. Approximately 1 in 68 children in the United States have autism. Some other facts are that boys are much more likely to develop autism opposed to girls and a fact that is somewhat startling is the fact that parents whose first child has autism, there is a 2-18% chance that the second child will also develop autism.

Autism and down syndrome are very common genetic disorders that affect a person's physical and developmental function. Many medical conditions follow when a person has one of these conditions such as congenital heart disease, gastrointestinal problems, opthamologic problems, respiratory problems and neurological problems. Even though down syndrome and autism vary with similarities they are also very different genetic problems. When a person has down syndrome they are often very social and outgoing. When a person has autism their communication skills are very weak. The pictures below show the chromosomal problems that appear with down syndrome (left) and autism (right).

“Researchers say they’ve found clear and direct evidence that autism begins during prenatal brain development.” Although there isn’t a certain test out yet to diagnose a baby in the womb with a probability that they