Genetics Abnormal Amnio Genetic Counseling And Prenatal Testing

Front 1

Dysmorphology definition

Back 1

study of abnormal form of birth defects to correctly diagnose a child

Front 2

common malformation show that first degree relatives are 10-40 fold higher to get it than the general population

sex, family history of malformation and severity can influence this risk

Back 2

for risk of recurrence of single congenital malformation take:
medical history
family history
phys exam
"risk figs" based on the same pop of proband

Front 3

Folic acid and pregnancy

Back 3

help alleviate neural tube defects, classic ex of multifactorial causation

Front 4

multiple malformation
evaluation

Back 4

family/pregnancy history, detailed exam, consulting databases, examining relatives, lab work up (ie chrom analysis)

Front 5

GENETIC TESTING COMPUTER EXERCISE

Back 5

on genetics webpage doooo iiiiitttttttt

Front 6

What is the indication for offering amniocentesis or CVS?

Back 6

high risk groups, less availability, costly, risks, prior/current obstetric history, maternal age, family genetic syndrome, carrier screening, multiple miscarriage

Front 7

Carrier Screening
(screen mom/dad to see if carrier)

Back 7

for autosomal and x-linked recessive, and ethnicity screening

Front 8

Preimplantation genetic Diagnosis (PGD)
purpose
indication
procedure
risks

Back 8

test for chromosomal abnormalities in embryo before implantation
Indication -age of mother, infertility treatment, high risk for genetic syndrome,

procedure - blastomere biopsy, single cell removed

risks - testing not available for all genetic mutations, expensive, possibility for error

Front 9

FIRST study
screen or diagnostic?
procedure
timing
detection rates

Back 9

screening


procedure - biochem markers PAPP-A and free hCG with two ultrasound (nuchal translucency and crown rump length) - better ultrasound

Timing - 9 weeks to 13 weeks 6 days, First trimester

Detection - screen for risk of downs, 18 and 13, rates are dependent on lab,

Front 10

MAternal serum screen
procedure - what are the biochem markers in a triple screen?

timing

results

Back 10

procedure - blood triple screen for AFP hCG and uE3(unconjugated estriol), can also look at inhibin A and ITA(invasive trophoblast antigen)

timing 14-21 weeks

results - trisomy 21 18 and NTDs, levels expressed as MoM(multiples of the mean) and should be 1, screen positive or negative

rates - not as good as FIRST

Front 11

Level II ultrasounds
procedure
timing

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Screening - see cleft lip, heart defect, maybe a chrom abnormality, offer invasive testing
single transducer generated image

timing - 18-24 weeks
soft markers for chromosomal abnormalities

detects 95% of ONTD's

Front 12

CVS
screening or diag?

timing

uses and results

Back 12

diag

timing - 9-12 weeks, 10-12 weeks, 10 wks-13wks 6 days

uses/results: detects 99% of chrom abnormalities, biochem/dna(single gene)/chrom analysis, cannot id single gene disorders unless have a gene marker, mosaicism, birth defects seen before 10 weeks gestation, miscarriage 1%

1/200 risk - about the same as amniocentesis because babies die in between cvs time and amnio time

Front 13

Amniocentesis
Procedure
timing

uses/results

Back 13

sample amniotic fluid
SCREENS for NTD's, ultrasound is DIAGNOSTIC

Timing - 15-24 weeks 16-20, SECOND TRIMESTERS

uses/results - chrom/dna/biochem analysis (including AFPlevels. highlevels = ONTD screening, low = trisomies) , 99% of chrom abnormalities

miscarriage 1/200, transmit hiv, rh isoimmunozation

Front 14

PUBS percutaneous umbilical blood sampling

procedure
timing

Back 14

sample umbilical vein for fetal blood

timing - after 18 weeks
Uses - diagnostic and therapeutic, in utero infection, karyotype, Rh incompatability

Front 15

if you have a downs syndrome child what is your risk of having another?

Back 15

1%, 1/100, so offer amnio/cvs

Front 16

what is the risk if you have 14/21 translocation of having downs?

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mother - 10/15% empiric risk, so offer cvs/amnio

Front 17

35 women at 6 weeks gestation, what would you suggest?

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offer CVS(need really high skilled operator), offer AFP with CVS cause dont get NTD detection, or amniocentesis

Front 18

22 year old woman with no sig history

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FIRST, or maternal serum screen