Okay class, today we will be reviewing some of the things we have learned in our recent exploration into Biology. The first lesson being genetic and sex linked disorders.
A genetic disorder is a problem or abnormality caused by a mutation or error on the genome. This is present from birth. A sex linked disorder is any chromosomal disorder where the mutation or error is present on the x or y chromosome.
I'll give you some examples of sex linked disorders, the first one being Hemophilia, this is a condition where blood does not clot normally. It is caused by missing proteins and has no given cure. It comes through 1 in 4,000 births.
The next one would be down syndrome, which occurs through an error in chromosome 21 and occurs from 1 in 700 births, but this number can increase when age increases. This gives the offspring different facial and physical body features along with possible slower thinking.
Another genetic disorder we have learned was Edward's Syndrome. This is when you have a problem with chromosome 18. The probability of someone having it is 1 in 5,000 children. There are some mental and physical handicaps. And most individuals with Edward's Syndrome do not survive their first year
The next one we will re discuss will be Turner Syndrome. The probability of someone having it is in a 1 in 2,500 births. This is the second most common chromosomal disorders, second to down syndrome. Symptoms vary form severe learning and physical disorders to almost no external abnormalities. The sex chromosomes were XO instead of XX.