CNS development and genetics

Question 1

what intrauterine causes can affect CNS development

Answer 1

maternal health and disease, trauma and infection, placenta function and placenta nutririo

Question 2

what extrauterine causes can affect CNS development

Answer 2

physical factors eg nutrition / emotional eg neglect or stimulation / exposure to drugs

Question 3

when does the embryonic period end

Answer 3

conception - week 9

Question 4

what are the 2 layers of an embryo

Answer 4

epiblast and hypoblast

Question 5

how do cells migrate through the primitive streak and node

Answer 5

nodal signalling

Question 6

what is gastrulation

Answer 6

formation of germ layers

Question 7

what do the ectoderm, mesoderm and endoderm go on to become

Answer 7

ecto: skin, nails, neural tissue / endo: muscle, cartilage, bone, vascular / meso: organs

Question 8

when does the neural tube form and what does it become

Answer 8

days 20-27 and becomes spinal cord, brain and ventricles

Question 9

when is the foetal period

Answer 9

9 weeks to birth

Question 10

what cells proliferate to form the neurocortex in the feotal period

Answer 10

neural progenitor cells

Question 11

what makes up the neuronal network

Answer 11

axons and dendrites

Question 12

what are the 2 stages that happen in brain development after birth

Answer 12

proliferation and myelination

Question 13

what neural tube development problems can arise

Answer 13

spina bifida and anencephaly

Question 14

what issues can arise from failure of brain vesicle formation

Answer 14

holoprosencephaly and double cortex

Question 15

what does the PLP1 gene make and where is it found

Answer 15

myelin proteins in CNS - found on X chromosome

Question 16

how can you obtain DNA in utero from the placenta

Answer 16

chorionic villus biopsy

Question 17

how can you obtain DNA in utero from skin/ urine cells of the baby

Answer 17

amniocentesis

Question 18

what can non-invasive paternal testing (NIPT) detect and how do you do it

Answer 18

foetal DNA in maternal serum: can identify sex and trisomy but rarely deletions or genes

Question 19

what invasive testing can identify chromosome abnormalities

Answer 19

chromosome microarray

Question 20

what invasive testing can identify single gene changes

Answer 20

PCR and next generation sequencing

Question 21

when can abortions normally take place until

Answer 21

24 weeks

Question 22

what extreme cases can warrant abortion after 24 weeks

Answer 22

anencephaly (without a brain), trisomy 18 (edward’s syndrome)