Female reproductive ageing Flashcards
What is anueuploidy?
An incorrect number of chromosomes.
What is anueploidy due to?
95% due to errors in the egg.
What happen to the risk of aneuploidy as women get older?
Increases.
What is a blastocyst?
When the egg is ready for implantation.
What happens when the egg is carrying aueploidy?
The egg goes into arrest befor implantation?
What happens when the egg goes into arrest before implantation?
Infertility
Miscarriage
Birth defects
When does the chance of getting pregnant begin to drop?
37
When does the risk of miscarriage increase?
35
What is trisomy?
An extra copy of a chromosome
What happen to the risk of a pregnancy with trisomy as women get older?
Increases.
What is trisomy 16?
Most common chromosomal cause of miscarriage.
What is trisomy 18?
Develop to term but die shortly after birth (Edward’s Syndrome).
What is trisomy 21?
Compatible with life (Down’s Syndrome).
Why are down syndrome cases going up?
Because women are getting pregnant at an older age.
Does the chance of pregnancy increase with medical assistance?
No.
What is an oocyte?
Immature eggs.
What are germ cells?
Cells are destined to transmit the genome to the next generation.
What happens to the stock of oocytes during ageing?
Declines after 30.
How are bivalent chromosomes maintained?
Cohesin
What is the function of Rec8?
Hold sister chromatids together
How are bivalent chromosomes converted to single copy genomes?
Bivalent stabalized by cohesin.
Monopolar attachment of sister chromatids.
Separase cleaves Rec8 on arms
Sgol2 protects centromeres.
Biopolar of sister centromeres, rec8 is deprotected.
What is the function of meikin in mammals?
Mono attachment of sister chromatids.
What are shungoshin proteins?
Protect cohesin at the centromere by recruiting phosphate PP2A.
What is the biggest age problem in female reproduction?
Premature loss of centromeric cohesion.
