Description
GGA POC SNP (single nucleotide polymorphism) microarray is a genetic testing for miscarriage to detect chromosomal abnormalities in POC (products of conception). It is a type of DNA array which is designed with high density (copy number variation) CNV+SNP probes to detect small variations across the whole chromosome set. The detection rate is higher than karyotyping (G-banding) and traditional oligo-microarray.
Overview
Studies have shown that 15-20% of pregnancies end in miscarriage. About 5% of couples have recurrent miscarriages. There are various causes for recurrent miscarriage including lifestyle factors, immune factors and etc. However, half of miscarriages are due to chromosomal abnormalities in the embryo. GGA POC SNP Microarray with both CNV and SNP markers could identify genomic copy number changes and homozygosity, such as Absence of Heterozygosity (AOH), Uniparental Disomy (UPD) and triploidy, to help determine the embryonic genetic causes of miscarriages.
References:
- Stock S: Miscarriage, National Institute of Health; (2012) Retrieved 2013-09-01.
- Stephenson M, Kutteh W. Evaluation and management of recurrent early pregnancy loss. Clin Obstet Gynecol (2007) 50: 132-145
- Rai R, Regan L, Recurrent miscarriage. Lancet (2006) 368:601-11
Find out the underlying genetic causes of miscarriage can help with:
- Clarify recurrence risk
- Adjust reproductive plan
- Alleviate anxiety and psychological burden due to uncertainty and self-guilt
When to consider POC SNP microarray?
- Recurrent miscarriage (including blighted ovum and cessation of embryonic development).
- Familial history of congenital abnormality.
- Previous pregnancy with chromosomal abnormality.
- Fetal structural abnormality on ultrasound.
- Parent(s) with chromosomal balanced translocation.
- Stillbirth/ Prolonged stillbirth.
- Want to know the cause of miscarriage.
Sample Requirements:
- Umbilical cord: >1cm
- Placenta (including 50mg chorionic villi): > 1cm³
- Fetal tissue (excluding whole fetus)
Do not place in formalin, formaldehyde or alcohol
GGA POC SNP Microarray with both CNV and SNP markers could identify genomic copy number changes and homozygosity, such as Absence of Heterozygosity (AOH), Uniparental Disomy (UPD) and triploidy, to help determine the embryonic genetic causes of miscarriages.
Why choose GGA POC SNP microarray?
- Combines copy number markers with SNP markers at a high density to provide the highest resolution and coverage.
- Able to detect more chromosomal abnormalities such as AOH, UPD and triploidy in one test.
- Able to identify maternal cell contamination.
- Cell culture is not required to avoid culture failure.
- Provide comprehensive genetic counseling support to clinicians.
- CAP-accredited laboratory with over 12 years of experience in genetic testing.
- GGA clinical studies^ yield a rich collection of genetic and clinical data on SNP microarray.
^References:
- J FORMOS MED ASSOC. Mar 2019, 118(3), 739-742
- Pediatrics and Neonatology. (2020) 61, 343-345
- Acta Obstet Gynecol Scand. 2020 Jun;99(6):775-782.
SNP Microarray is the preferred platform in POC testing due to its high resolution and coverage
In 2016, the American College of Obstetricians and Gynecologists (ACOG) and the Society for Maternal-Fetal Medicine (SMFM) issued that chromosomal microarray analysis typically can replace the need for fetal karyotype.
SNP-based chromosomal microarray for products of conception:
- Yields a higher rate of results compared with karyotyping
- Can identify maternal cell contamination to decreasing false-negative results
From Genetics in Medicine 2017:
- Analysis of POC specimens by karyotyping fails in 20-40% of cases. SNP-based chromosomal microarray is a robust platform, with successful results obtained in >90% of cases.
- SNP-based chromosomal microarray can identify aneuploidy, polyploidy, whole-genome homozygosity, segmental genomic imbalances, and maternal cell contamination, thus maximizing sensitivity and decreasing false-negative results.
- Understanding the etiology of fetal loss enables clarification of recurrence risk and assists in determining appropriate management for future family planning.
