Genetic disorders occur when mutations affect your genes. The mutation doesn’t always mean you will end up with disease. There are many types including single gene, multifactorial, chromosomal. It can be, for example, chromosomal that these types affect the structures that hold our genes’ DNA within each cell that is called chromosomes and we could have complex or multifactorial diseases. These disorders stem from a combination of the mutations and other factors. They include chemical exposure, diets, certain medications, tobacco or alcohol use and we could have the single gene or monogeny -this group of conditions occurs just from a single, very little gene mutation and it is important to know about mitochondrial diseases. Mitochondria are like little batteries that make energy within each cells, the energy source is a chemical called adenosine triphosphate ATP so, organs like the brain, heart, liver can survive without the ATP so if one of the genes in the mitochondria is altered and the condition is inherited but just only from the mother.
You can follow inheritance and families, obviously paternity testing seeing if the child who’s the father of the child. You follow the DNA down to the child. What you get in paternity testing is it’s not always exactly the same. You get a match to the father. But if you look at enough DNA, you will see that there are slight changes in the child. That’s happened in the man’s sperm. There are mutation hotspots. A particular example of that is a gene called FGFR3. There’s one base pair change, which I think is a G to a C. It’s responsible for dwarfism, achondroplasia, and 80% of dwarves are not from a family of dwarfs. It has just occurred. It usually only occurs from the man’s side from the male sperm and in older men. It seems to be very prone to mutation. If the sperm has got this mutation, they are at an advantage over the other sperm in the man’s testicles. The human race is always going to have achondroplastics born.
