Throwback Thursday, where, essentially I post old writing samples, essays and short stories that I dig up from my pile of hoarded papers and school assignments or from the depths of my computer. So everyone can see how my writing has changed/improved over the years.
For this particular assignment, we drew chromosomes from a hat to write about the disorder a trisomy of that chromosome would cause.
I originally drew 21 but everyone else reveled, saying it was unfair since I wouldn’t have to research it (my sister has Down’s Syndrome – also known as trisomy 21) so I traded with my best friend for trisomy 15. All the science here is as accurate as a 14 year old could get.
Dear Soon-to-be Parents,
I have finished reviewing your child’s karyotype, and I regret to inform you that I found a genetic abnormality. As you know all human beings have 46 chromosomes. In your son’s case he has 47 chromosomes, an extra chromosome, the 15th to be precise. This is also called trisomy 15. This additional chromosome can cause one of two genetic syndromes. Trisomy 15 can cause either Prader-Willi’s syndrome (PWS) or Angelman’s Syndrome (AS). PWS occurs when the extra chromosome comes from the mother. AS occurs when the extra chromosome comes from the father. Unfortunately a karyotype does not tell us where the extra chromosome came from and thus I cannot tell you which disorder your son will be born with. Both syndromes also result in miscarriages, but at this stage in pregnancy that is highly unlikely. As you are entering the third trimester, an abortion is also not a viable option so I would like to take this opportunity to provide some education and prognosis so you can help your son grow and develop to the best of his potential.
Some common symptoms to both disorders are: delayed growth and development, mental retardation, hypotonia (weak muscle tone), and characteristic facial features. The severance of these symptoms varies from child to child.. Chromosome 15 codes genetic information used largely by the brain, specifically in muscle movements, as well as, eye and skin color. The maternal chromosome is usually the most active, thus, with Angelman’s syndrome, the extra paternal chromosome manifests in certain symptoms. Angelman’s causes developmental delays, especially physically. Fine motor skills are underdeveloped and they have short attention spans. Those with Angelman’s frequently exhibit hypopigmentation, which causes their skin, eyes, and hair to be significantly lighter than the parents’. Children with Angelman’s generally have poor verbal skills, though their non-verbal communication is generally better than their peers. They are described as “excessively happy and always smiling”. Children with Angelman’s can live independent, happy lives with the proper assistance and care. They live well into adulthood and can have children of their own, though it is hereditary.
As for Prader-Willi’s syndrome, an extra maternal copy is activated. Common symptoms include: extreme, insatiable appetite (polyphagia), delayed to no pubescent growth (hypogonadism), extremely weak muscles, and hormone imbalances. People with this condition typically find it hard to reproduce. They have distinct facial characteristics, including: thin upper lips, almond shaped eyes, lighter skin, and a downturned mouth. Joints are usually loosely extended and sex organs are slow in development. As with Angelman’s, children with Prader-Willi’s have trouble learning and speaking. Due to their insatiable hunger, they are prone to huger pains, and obesity. This can cause severe sleeping and behavioral problems. Nearly all with Prader-Willi’s live well into adulthood, but many rely on drug therapy to suppress the worst of the symptoms. Both disorders are linked to having a lower than average intelligence.
You may be wondering how this could have happened to your son, wondering how he ended up with three chromosome 15s instead of two. You may want to blame each other. Well don’t. It is just as likely to come from the father than the mother, and vise-versa. It isn’t either of your faults; it is a result of non-disjunction. Non-disjunction is, to put it simply, when in meiosis, the chromosomes that should separate, don’t. Usually, replicated chromosomes split, so each haploid cell/gamete has one copy. Non-disjunction can occur equally in males and females. When non-disjunction occurs, both copies of a chromosome enter one cell, and none enter the other. If this occurs in Meiosis I, then there is a 50% chance of a monosomy (having one copy of a chromosome) and 50% chance of a trisomy (having 3 copies, which is what happened to your son). If non-disjunction happens in meiosis II, then there is a 50% chance of a “normal” baby, 25% chance of monosomy, and 25% chance of trisomy. It is not your fault, and you are not the only parents to go through this, your son is not the only one with this disorder (which ever it may be). About 1 in 1000 pregnancies have chromosomal disorders. And while there isn’t a cure, there are ways to help your son.
Treatments for both Angelman’s and Prader-Willi’s are similar. One noticeable difference is that children with Prader-Willi’s require more hormone and drug treatments. Hormone treatments are used to help the child develop normally, and to trigger puberty if it does not occur naturally. Drug treatments are also used to treat the hunger pains. Many children follow special diets that are “low in calories but high in proteins, fiber, and various essential nutrients” so that they do not become obese. Other treatments for Prader-Willi’s are the same as those for Angelman’s; they focus mainly on making the symptoms caused by the disease manageable.
Early Intervention is the key to minimizing the effects and increasing your son’s chances of success. Early Intervention programs provide children a mix of speech, occupational, and physical therapies, among other things. This starts in infancy and can help a child with these disorders to develop skills similar to their “normal” peers. This therapies can help a child with a developmental disability reach milestones sooner than they would on their own. Children who go through early intervention are more capable and show less extreme symptoms than those that don’t. Children with chromosomal disorders often require more specialized learning environments than public school can offer, there are special schools these children can attend to aid their education. Here in south Florida, schools such as “The Learning Experience” are specifically for taking care of those children with special needs. And while these schools can be expensive, scholarships and other programs are available such as the McKay Voucher here in Florida. Feel free to contact me, or any of my co-workers for additional information. And remember, your son is special. He’s going to need a little extra help, but he’ll love you the same as any other baby.
Dr. Samantha B. (Last name redacted)