Please enable JavaScript.
Coggle requires JavaScript to display documents.
Chromosomal abnormalities (mosaicism (germline (effecting only gametes,…
Chromosomal abnormalities
mosaicism
regions of tissue within an individual have different chromosome constitutions
caused by an error in cell division early on in embryo development
germline
effecting only gametes
offspring will have full disorder
individual is unaffected by the disorder
somatic
not effecting gametes
will not be passed on to offspring
individual is affected by the disorder but often to a lesser degree than the full disorder.
numerical abnormalities
euploid
containing a multiple of 23 chromosomes
polyploid
euploid but with more than 46 chromosomes
triploidy
most common
when two sperm fertilise the same egg
often results in miscarriage
tetraploidy
results from failure to complete the first mitotic division
results in an nonviable pregnancy
aneuploidy
the opposite of euploid
when one extra copy of a chromosome this is known as trisomy
trisomy 21 is down syndrome
trisomy 18 is Edwards syndrome
XXY is Klinefelter
loss of one chromosome is known as monosomy
X0 is Turner Syndrome
normally fatal
can result from non-disjunction
when chromosomes don't separate during anaphase