Trisomies and syndromes Flashcards
What syndrome is associated with trisomy 13?
Patau Syndrome
What syndrome is associated with trisomy 18?
Edward’s Syndrome
What syndrome is associated with trisomy 21?
Down Syndrome
What is triploidy?
The presence of an additional set of chromosomes in the cell for a total of 69 chromosomes rather than the normal 46 chromosomes per cell
A condition that affects only females, results when one of the X chromosomes (sex chromosomes) is missing or partially missing.
Turner syndrome
Which syndrome is associated where boys and men are born with an extra X chromosome?
Klinefelter syndrome
Women in their late __s and ____s have a higher chance of trisomy conditions occurring
30s and 40s
What percentage of people with Down syndrome will experience some delay in their development and some level of learning disability?
100%
Three copies of chromosome 21 instead of two is which syndome?
Down syndrome
Which trisomy is associated with the father’s sperm or the mother’s egg cell contains the extra chromosome?
Trisomy 21
Down syndrome
What is it called when an extra chromosome spontaneously appears as the embryo develops?
Mosaic down syndrome
Physical characteristics of down syndrome may include:
- slight upward slant of the eyes
- small fold of skin on the inside of the eye (epicanthic fold)
- small white patches on the edge of the iris of the eye (Brushfield spots)
- rounded face or flat profile
- usually smaller and weigh less at birth than others
What syndrome is three copies of chromosome 18 instead of two?
Edward’s syndrome
Characteristics of Edwards syndrome includes:
- physical irregularity of the kidneys, ureters, heart, lungs and diaphragm
- cleft lip or cleft palate
- small skull (microcephaly)
- malformations of the hands and feet – including missing thumbs, club feet and webbing between the fingers and toes (syndactyly)
- neural tube defect, where the spinal cord, meninges and blood vessels protrude through a gap in the vertebrae (myelomeningocele)
- malformations of the sex organs
Survival rate for Edwards syndrome is _____.
Poor
What syndrome is associated with three copies of chromosome 13 instead of two?
Patau Syndrome
Characteristics of Patau syndrome includes:
- small skull (microcephaly)
- an abnormal opening in the skull
- malformations of part of the brain
- structural defects of the eyes
- cleft lip or cleft palate
- additional toes or fingers (polydactyly)
- congenital heart disorders, such as ventricular septal defect
- neural tube defect, where the spinal cord, meninges and blood vessels protrude through a gap in the vertebrae (myelomeningocele)
- malformations of the sex organs
Survival rate for Patau syndrome is _____.
Poor
Signs of trisomy during pregnancy includes:
too much amniotic fluid surrounding the baby (polyhydramnios)
only one umbilical cord artery
a smaller than expected placenta
the baby is small for its gestational date
the baby is less active than expected
congenital defects, including cleft palate or heart irregularities, are picked up during ultrasound scans
Prenatal tests that can help detect trisomy disorders include:
ultrasound scans – sound waves are used to create a picture
maternal serum screening – a specialised blood test
amniocentesis – a sample of the amniotic fluid is taken and examined
chorionic villus sampling – a sample of cells from the chorion, the tissue that will ultimately become the placenta, is taken and examined
non-invasive prenatal testing (NIPT) – a screening test that measures fetal DNA circulating in the mother’s blood.
XXX
Trisomy X
XXY
Klinefelter syndrome
