Why do people who have down syndrome all have similar physical appearances?!


Question: Why do people who have down syndrome all have similar physical appearances!?
its pretty obvious when someone has down syndrome because they all have similar faces if that makes sense!.!.but why is this!? i know what causes down syndrome, chromosomal wise, but i dont really understand why they look alikeWww@Answer-Health@Com


Answers:
The jury is still out on that, but one of the most widely accepted theories involves the specific chromosomes involved!. The 21st chromosome (the one that's been triplicated and is the extra one for them) holds approximately 200-250 genes on it!.!.!.and those extra genes are believed to cause the existing ones on the other chromosomes to "overexpress" themselves!. It basically heightens the effects that would already have been put there for a "normal" person, and by doing so, it causes the physical & mental features to change!. We know that each specific chromosome controls the same thing for each person so basic genetic coding is pretty much the same for every human!. therefore, because it is the same chromosome every time that replicates in those with down's, it stands to reason that the mutation will cause the same differences in each of them: one gene of that chromosome may cause cataracts, one causes skeletal deformities, one causes mental retardation, one disrupts metabolism, etc!.Www@Answer-Health@Com

You are correct that DS is a chromosomal disorder!. it is that very thing that causes a skew in physical attributes!. It not only affects physical growth and facial appearance, it also affects cognitive abilities!. My guess, given my limited knowledge of genetics is it would have to do with trisomy 21(extra copy of genetic material)!.!. which accounts for most DS cases!. The disorder itself is occurs at the genetic level!.!. genetics are the blueprints for how you will look physically(among other things)!.!. so therefore if a genetic disorder is present it is safe to assume that almost everything genetic will be affected!. I know this doesnt fully answer your question!.!. but take into consideration that DS is a genetic process that 9/10 times produces similar results!.Www@Answer-Health@Com

The genes that decide facial features are extra expressive, so all the people have similar muscle structures!.

This is a much simpler description of the above!.Www@Answer-Health@Com





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