Trisomy 16: The Story of Shayna Lange

Trisomy 16: The Story of Shayna Lange

Jared Rogerson

October, 2014

Genetic Disorders

Mr. Youell

Recently I have seen a lot of blogs and support websites for Trisomy 16, so I decided to write about this disorder. Trisomy 16 is a genetic disorder which is the main cause of First Trimester Miscarriages. A miscarriage is when a pregnancy naturally aborts itself, and can be caused by many different things, including Trisomy 16. A trisomy is where a group of chromosomes in a persons DNA have three of the same chromosome, instead of the usual two. In the case of Trisomy 16, the sixteenth pair of chromosomes is not a pair, but a threesome. This is usually caused by something called nondisjunction (see Fig2) which happens during Meiosis, and splits the chromosomes up wrong, making the gamete (male sperm or female egg) have three sets of chromosomes in it.

There are quite a surprising amount of blogs and support groups for this, which are catered towards parents who find out that there would-be child has Trisomy 16, and how to live with it and what to do. One such story from one of these blogs is about someone who actually survived Trisomy 16 passed birth, and is living an almost normal life. This child is named Shayna Lange, and she has Trisomy 16. She was born three months earlier than expected, and the doctors said that she would not survive until birth, let alone into her adult life. She had some speech disabilities early in life as well as being not up to par in Math, but she worked extremely hard and overcame this, eventually even graduating high school with a 3.2 GPA. She went on to go to college and is still alive and doing extremely well to this day.

Although Shayna is doing really well, that isn't the case for most fetuses or babies with Trisomy 16. According to trisomy16.org, Shayna is one in about 100 people  with Trisomy 16 that survived birth, and continued on into adulthood. This is very low considering that about 1% of all pregnancies have this genetic disorder, which is actually fairly high considering that it means that one in every one hundred pregnancies, the child will have Trisomy 16.

There are two different types of Trisomy 16; Full Trisomy 16 and Mosaic Trisomy 16 (see Fig1). Full Trisomy 16 is when every single cell in the body is affected, and it is incompatible with life, meaning that it is nearly impossible to survive past the First Trimester of pregnancy. This obviously resulting in a miscarriage.  On the other hand, Mosaic Trisomy 16 means that only some of the cells are affected, meaning that the fetus has a slim chance of surviving birth and continuing on afterwords.

The effects of Mosaic Trisomy 16 vary wildly depending on how many cells are affected, and where the cells that are affected are located. It can be anywhere from a perfectly normal developmental child, to some minor cognitive function issues, to serious brain problems, as well as some possible muscle or growth issues. Also most cases result in premature birth which can bring problems of its own; like the baby not having fully developed lungs or heart, as well as the possibility of different kinds of disorders.    

As you can see Trisomy 16 is a very serious and dangerous genetic disorder, but even so some children survive into adulthood and live almost completely normal lives. This depends on whether they have Full or Mosaic trisomy, because with Full trisomy it is impossible for the fetus to live to birth and beyond, but with Mosaic trisomy it is possible for the child to be born and live a full and fulfilling life.   

Figure 1:  Shayna Lange: Survivor of Mosaic Trisomy 16 who has lived a successful life to this point

Figure 2: what happens during nondisjunction to cause genetic disorders in a fetus