Embryology

Question 1

What is an issue with PB biopsy

Answer 1

Analysis of both PB is required to identify Meiosis 1 and 2 errors

Question 2

ASRM and sart recommend how many embryos to transfer
Picture

Answer 2

Euploid= 1 for all

Other non tested= 1, 38-40=2, 41-42=3

Question 3

Quality management(Qm) includes what

Answer 3

Qc, QA, QI and lab accreditation

Question 4

QC

Answer 4

Quality control
Trained personnel
Instruments calibrated
Environment, media reagents
Execution of techniques
Safety manuals
Records
Procedure manuals
Corrective actions

Question 5

Quality assurance qa

Answer 5

Monitor and evaluate quality of outcomes
Set thresholds
Kpis (critical indicators)

Question 6

Why are sperm good to freeze

Answer 6

Smallest human cell with small volume and large surface area
Little cytoplasm
Contain less total intercellular water than other cells
Exist individually, good for dehydration

Question 7

Sperm cryo temperature range where extra cellular ice formation occurs and induces extra cellular solid phase?

Answer 7

-5c— -15c

Super cool phase

Question 8

Standards for sperm banking established by:
Guideline by?

Answer 8

American association of tissue banks aatb

ASRM

Question 9

What causes numerical chromosome defects?

Answer 9

Nondisjunction- failure of homologus chromosomes to split during metaphase of meiosis

Question 10

Klinefelters

Answer 10

XXY
Azospermic
Small testis
Sperm available through tese

Question 11

Xyy males

Answer 11

Usually fertile
Aggressive behavior

Question 12

XX males

Answer 12

Genotype female
Phenotype male

Small testis
X blocks meiosis =azospermic
Sertoli only phenotype no sperm to retrieve

Question 13

Robertsonian translocation

Answer 13

Translocations b/t Acrocentric chromosomes (small too long bottom) long sections are translocated to other long section

Usually 13,14 14,15 13,21 or 21,22

Oligospermic
45 chromosomes

Question 14

AZF spermatogenesis gene microdeletions

Answer 14

AZFc= have sperm
AZF a and b= sertoli only, no sperm

Question 15

What is an aCGH

Answer 15

Array comparative genomic hybridization

Microarray recognizes unbalanced gains and losses, CNV( copy number variation) Fluorescence yellow= ok, green =gain, red=loss

Question 16

Whole chromosome

Answer 16

Aneuploidy

Question 17

Partial chromosome abnormalities

Answer 17

Translocations and deletions

Question 18

Micro deletions and copy number variants (CNV)

Answer 18

Duplications/ deletions in regions of DNA

Question 19

Point mutation

Question 20

Sexual determination disorders

Answer 20

Gonads fail to form during development due to gene malfunction

Need WT1 and SF1 for gonadal ridge to form
SF1 loss =sex reversal in XY

SRY and SOX9=required for testis differentiation (bio potential gonad towards testis)

Question 21

Nondisjunction (ND) vs Premature Seperation of Sister Chromatids (PSSC)

Answer 21

Maternal meiotic errors arise from both

PSSC- 90% maternal meiosis 1 erros result from this

ND- occurs at cross over

See picture

Question 22

3 steps of PGT-A detection

Answer 22

DNA amplification
Detection
Analysis

Question 23

Technology for 24 chromosome embryonic Aneuploidy screening

Answer 23

Comparative genomic hybridization (CGH)
Quantitative SNP array
QPCR
Nextgen

Question 24

CGH

Answer 24

Comparative genome hybridization

Metaphase chromosome, whole gene amplification, dna hybridized to metephase spreads

PBs or embryonic bx dna, labeled with fluorophore (red or green)

Increased brightness=trisomy
Decreased=monosomy

Takes 12hrs-days long time

Question 25

Quantitative SNP array

Answer 25

Whole genome amplification dna labeled with a fluorophore and each locus and copy number compared to other snps on the chip

Question 26

Quantitative SNP array

Answer 26

Whole genome amplification dna labeled with a fluorophore and each locus and copy number compared to other snps on the chip Good for microdeletions

Question 27

ArrayCGH

Answer 27

CGH on a microarray Not metaphase chromosomes, dna is hybridized with specific segments from each chromosome. Then measures at a specific segment of the chromosome and replicates each segment.

Question 28

QPCR

Answer 28

Quantitation of the number of amplification cycles required to attain a reliably detectable signal for amplification at a specific locus 4 loci on each chromosome and measures in quads (24 chromosomes x 4 loci x 4 rxns) 384 reactions Amplification and quantitation concurrent so is fast results Taq polymerase

Question 29

Next gen sequencing

Answer 29

Taq polymerase to amplify whole genome to create small fragments of dna- each fragment is sequenced and aligned based on sequence of nucleic acids with sequences from a database. Segment being analyzed is a depth More reads = trisomic Under representation= monosomic

Question 30

PGT-SR-

Answer 30

Balanced translocations detection

Question 31

PGT-M

Answer 31

Single gene defects For couples with a known risk for a particular genetic disorder

Question 32

What maintains meiotic arrest Intra oocyte

Answer 32

cAMP and cGMP