Genetics 101

OK, so a few people have expressed an interest in the exact base level nature of B’s disorder, right down to what precisely it is that causes him to be so different from all of us neurotypicals. Neuro=to do with brain; typical=usual, regular, common- sorry folks, in the world of genetics you and I are pretty damn boring. Let’s picture an ice-cream sundae. Proportionately us neurotypicals would be the ice cream and the special atypical a=not, typical=see above lovelies the sprinkles. So first up, people with B’s condition are RARE. The prevalence is estimated to be around one in thirty or forty thousand. So, for every 40,000 babies born, 1 might pop out like B. To give you an idea in real terms, Down Syndrome occurs once in every thousand births, DiGeorge (considered a relatively rare chromosome disorder) occurs once in every four thousand births. You can see where I’m going with this. If I asked you how much information you know about cats you would probably reel off ten facts without an issue. Furry, annoying, crap all over my flowerbeds, come in a range of colours, make nasty screeching noises when they get down and dirty etc. Let’s try the same thing with the Indonesian civet. Unless you are a closet junior bake off fanatic (I’m out and I’m proud!) or you happen to own an exclusive café company, you’ll likely have no idea what I’m talking about. The civet is a cat-like creature famous for it’s expensive coffee producing shit. Yes, literal brown stinking shit. It eats coffee beans and they reappear hours later, magically transformed into the world’s most expensive coffee, cunningly disguised in the form of plain old shite. Gives a whole new meaning to the world’s crappiest cup of coffee. Anyway, I digress. My point is the rarer something is, the less we tend to know about it. Rarity and uniqueness in this context sucks.

OK, second up, B’s condition is a clinically identifiable syndrome. Clinically identifiable=recognisable by defined and consistent medical observations, syndrome=a combination of common symptoms specific to and indicative of a certain medical issue. Duplication 15q syndrome is suspected when an individual exhibits certain characteristics universal to the syndrome, and confirmed with a specific blood test to determine karyotype. Karyotype=the number and appearance of chromosomes in the nucleus in a cell.

Individuals with dup15q syndrome have a different genetic make-up than you and me. We have 46 chromosomes chromosomes=threadlike structures made from DNA in each cell in our body. They are arranged in 23 pairs, and on that sweet, unforgettable night however many years ago your dad generously donated the yin of each pair, and your mum matched his generosity and donated the counterpart yang. Ta-da! Nine months on and a baby human emerged, complete with 46 chromosomes in each little building block cell. Cell=the smallest structural unit of a living thing.

Sometimes, this amazing process of mixing and matching goes a little bit haywire. There is a lot of speculation on why this happens, but currently every idea remains firmly in the theory camp and has yet to gather evidence to cross that bridge into fact territory. What we do know though, is it occasionally gets screwed up.  In the case of B his chromosome number 15 from me decided to go the extra mile and copy itself. More specifically, an area of chromosome 15 copied itself 4 times. ‘Dup’ is a bit of a misnomer here, but it infers the idea of duplication, or too much. So dup=too much, 15=the chromosome that has too much material, syndrome=see above. Don’t worry too much about the q part; it just refers to the specific location on chromosome 15 where the copied bit originated from. I hope I haven’t lost you yet, bear with me!

So every individual diagnosed with duplication15q syndrome shares one thing in common- they all have too much chromosome 15 material floating around in their cells. Here’s the bit that gets even more complicated. The amount of material that’s copied loosely correlates with the severity of that particular individual’s symptoms. Loosely meaning it doesn’t always work out that way. If you think of chromosome 15 as a toy train track with lots of different segments, there is one particular segment, which seems to be more unstable than the others. More unpredictable. It’s kinda the anarchist rebel headquarters of chromosome 15. This region contains genes genes: segments of a chromosome that give instructions to control physical features of that person; eye colour, brain development, hair thickness etc. which seemingly have a big impact on a person if they are messed with. It even has it’s own name since it’s so infamous in the genetics world. The PWACR. How very rock n’ roll. In dup15q people this rebel section (the PWACR) has gone it’s own sweet way and copied itself; sometimes once, sometimes twice, sometimes multiple times and depending on how it was feeling at the time did it one of two ways. Either it made a separate impressive new mini-chromosome, complete with pretty mirror image upside down copying, or it decided to stay within the original chromosome and try and sneak an extra copy in unnoticed. It seems to like doing the first pretty thing more often. When an extra copy is made within the existing chromosome it tends to be a carbon copy of the rebel section without all the upside down and mirror image nonsense. So people with the condition can have either 47 chromosomes (with the impressive pretty extra rebel section making up the 47th) or they can have 46 (with a sneaky extra rebel section snuck in number 15).

But you know us Parrs; we don’t do things by halves. We had to go one step further, and this is no exception! B has a combination of both of the above, never before recorded in the UK, a stand alone first on the British genetics database. Apparently his rebel headquarters was extremely indecisive on the whole section copying issue, and ended up copying structurally as an extra chromosome (the pretty mirror image upside down thing) but remaining within his original chromosome 15. We just can’t help but be different- it’s in the genes. Do you see what I did there? Moving swiftly on…

What does all this mean? Well, in all honesty we are a long way from fully knowing. What we do know though is that the extra material messes up the instructions from the genes, creating havoc in the growth and development of a person right from that initial yin-yang moment. The classic symptoms of the syndrome are low muscle tone (floppiness), sensory integration disorder, autism or autistic tendencies, certain physical features (all our kiddos are incredibly gorgeous), epilepsy, attention deficit issues, lack of speech or communication problems, and learning difficulties. Some kids are more severely affected than others, and it’s not always easy finding universally appropriate interventions because a thousand other factors come into play too- what type of personality a child is, or how much money their parents have to throw at new therapies for example. One thing that is abundantly clear; as parents we have had to become experts on our children. We’ve learned to communicate without need for words, to understand the subtle intonations in our child’s frustrated behaviour, to differentiate a seizure from a stim, to believe in ourselves as the specialist on our child. And when the whole world seems oblivious, that shit is pretty damn hard.

I’m hoping by writing this, maybe a little corner of the world will be a little less oblivious, and accept people regardless of their disability. No amount of therapy or medicine will ever be able to ‘fix’ B; his condition is inseparable from who he is. That extra genetic material is in every single cell of his body. The seizures, they suck. The frustration of him not being able to communicate? I’d take that away in an instant if I could, along with all the other crap that causes life to be so much harder than it should be. But I don’t think he needs fixing. The typical worldview on disability? Now that could do with some definite attention.