Science Behind Gender Test
Pink or Blue® is based on the latest DNA gender testing technology. The test analyzes fetal DNA found in the mother’s blood. The Science is Proven…
- PCR detection of cell-free circulating fetal DNA in maternal plasma and serum (Lo et al. Lancet 1997; 350:485-7)
- Earliest detection of fetal DNA: 5 weeks of gestation (Prenatal Diagnosis, 2003; 23: 1042)
- Source of fetal DNA? Passive diffusion across placental barrier (van Wijk et al. Clinical Chemistry, 2000; 46:729-731)
In a natural process, fetal cells die and pass into the mother’s bloodstream. As these cells break down, fetal DNA is released into the mother’s own circulatory system. Pink or Blue® can detect the baby’s DNA as early as 7 weeks into a pregnancy (approximately 10 weeks from the last menstrual period).
The scientists at Consumer Genetics have created a technology that relies on this natural process and which can accurately predict gender. The scientists developed an reliable process which is now used commercially, in doctors offices and medical centers, to easily and conveniently determine an unborn baby’s sex as early as 7-weeks post-conception. The DNA test examines the presence or absence of male-DNA found in the mother’s bloodstream. Click Here to Calculate your Pink or Blue Eligibility Date.
The human Y-chromosome is only found in males. Pink or Blue® looks for Y-chromosomal DNA in the mother’s blood using a technique called Real-Time Polymerase Chain Reaction (RT-PCR), which amplifies small amounts of DNA to achieve easily detectable levels.
Pink or Blue®’s technology is more sensitive than previous techniques and thus can provide an accurate answer from just three drops of maternal blood (average amount/drops to fill one circle on the DNA preservation card located in the kits). Although results can be obtained from only one circle, Consumer Genetics request that the expectant mother fill all three circles.
The DNA specimens are always tested twice, in parallel, for quality assurance and reliability purposes. Male-specific DNA will be present in the specimen if the baby is a boy. This is because the mother does not carry the male-specific Y-chromosomal DNA. If there is not male-specific DNA detected by the Pink or Blue® process, results indicate a high probability that the mother is expecting a girl. All DNA samples are analyzed in the Consumer Genetics laboratory, located in Sunnyvale, California.
The classic study validating the PCR method for detecting fetal sex was published in the Journal of Human Genetics in 2005. Scientists in Italy (Galbiati et al) obtained blood from pregnant women at different stages of pregnancy and isolated fetal DNA as early as 5 weeks of pregnancy. The isolated fetal DNA was amplified and analyzed using PCR. They studied 1,837 pregnant women. This included women with previous pregnancies, miscarriages and live births. The test results were confirmed after the baby’s birth and their study had a 99% accuracy rate at correctly predicting gender. Note: The 99% accuracy rate in the Galbiati research study was performed under controlled conditions. The Pink or Blue® accuracy rate in the hands of the consumer is calculated to be greater than 95%, based on internal survey.
Pink or Blue® is highly accurate in determining the presence of male DNA in the mother’s blood. However, there are a few instances, such as a recent blood transfusion, multiple-child pregnancies, previous male-child pregnancy, or a bone marrow transplant, which may also contribute to the presence of male specific DNA in the maternal blood. although unlikely, these instances do occur, and may lead to false-positive results.