Trisomy 18

Trisomy 18

All living things on Earth are made of genetic material called DNA or deoxyribonucleic acid. When mass amounts of DNA are tightly wound together, they form one of our forty-eight distinct chromosomes, which pair together to form twenty-three pairs of autosomal chromosomes and one pair of sex chromosomes. When there are more than two, less than two, or any abnormality between a pair of chromosomes, genetic diseases can occur. 

Trisomy eighteen, or Edward Syndrome, is a genetic disease in which there is one extra copy of a person’s eighteenth chromosome. This defect stunts the growth of the fetus and is normally fatal before birth or within the first year of life. The statistics on Trisomy eighteen are heartbreaking: only 60-75% of children survive the first twenty four hours after their birth, 20-60% are able to survive for one week, 22-44% survive after one month, and a saddeningly-small 5-10%  are able to survive for over one year. Moreover, prospects for preventing this disease are lacking. A clinical method to prevent or cure trisomy eighteen does not exist due to it being a genetic disease.

Even if a person manages to survive the early obstacles of this incurable genetic disease, equally deadly roadblocks will plague them for the rest of their lives. According to David Perlstein’s research, a baby who manages to survive early stages of trisomy eighteen is doomed to experience intrauterine growth retardation, craniofacial features, and abnormalities of the jaw, skull, ears, and neck, and organs. 

There are three major variations of Trisomy eighteen: full, mosaic, and partial. The difference between the three lies in the number of extra chromosomes that are in each cell. Full Trisomy eighteen entails an extra chromosome eighteen in each cell, while Mosaic Trisomy eighteen means that there is an extra chromosome in only some of the cells. The third variant, Partial Trisomy Eighteen, is when only part of the third copy of chromosome eighteen is found in the cells.

Finally, here is a picture of my brother who had trisomy eighteen. He is the reason that I decided to research this topic for my Honors Capstone project during my 8th grade year.