The discovery was made one Hong Kong evening in 1997, but the scientific breakthrough wouldn’t come until a decade later in 2007 due to the persistence of Dr Yuk Ming Dennis Lo. But how did he come about this discovery, and what are the real benefits?
Hang on as we ride Dr Lo’s roller-coaster ride to this impressive discovery.
[fusion_builder_container hundred_percent=”yes” overflow=”visible”][fusion_builder_row][fusion_builder_column type=”1_1″ background_position=”left top” background_color=”” border_size=”” border_color=”” border_style=”solid” spacing=”yes” background_image=”” background_repeat=”no-repeat” padding=”” margin_top=”0px” margin_bottom=”0px” class=”” id=”” animation_type=”” animation_speed=”0.3″ animation_direction=”left” hide_on_mobile=”no” center_content=”no” min_height=”none”]Dr Yuk Ming Dennis Lo
Dr Lo’s first discovery was that the DNA of an unborn baby floats freely in its mother’s blood plasma — the yellow liquid that holds blood cells in suspension. And he was convinced that this DNA was a window into an unborn baby’s health and future.
But exactly how could this be proven? This was Dr Lo’s next hurdle. At that time, the medical world was not interested in his discovery because they thought that you could only use this information for sex selection. But Dr Lo believed differently, and he sought to prove it.
Out With the Old, In With the New
At that time, if information about a baby in its mother’s womb was required, they inserted a big needle through the mother’s tummy into her uterus to extract fluid from the amniotic liquid surrounding the baby in the womb, this procedure is called amniocentesis.
But this procedure carries a 1 in 100 risk for a miscarriage, and Dr Lo was determined to change that. So began the intensive research into foetal DNA that could be taken from a mother’s blood sample – at no risk!
A Scientist’s Persistence
Hence began Dr Lo’s eight-year search for foetal DNA inside a mother’s blood cells. But the number of foetal cells that enter this part of the maternal blood turned out to be very small, and the search had to be called off; well, until he read about how DNA from tumours were found floating within the blood plasma of cancer patients.
Applying this principle to his research, he figured out that if DNA were to be extracted from blood plasma, the blood sample would have to be boiled. And boil it, he did!
The process of boiling the sample destroyed proteins in the plasma — which could digest, and destroy the DNA — yet, leaving DNA that was unharmed. He then proceeded to test the mother’s blood plasma for fetal DNA, and where before the result from previous research had been disappointing, his first result in this case was staggering!
In his own words, he exclaimed:
I could not believe my eyes — the foetal DNA we had been looking for in the mother’s blood was in the part we had not looked in for eight years. It had been hiding there all along!
Any Application For This?
The medical world was still doubtful of his findings, except he could show that it could be used to test for Down’s Syndrome in unborn babies.
Down syndrome, by the way, is caused by a foetus having an extra copy of chromosome 21. Traditionally, the condition was diagnosed by looking at cells from a foetus and counting the chromosomes, and scientists didn’t believe a diagnosis could be made using cell-free DNA (cfDNA). But Dr Lo proved them wrong, again.
After another decade of dedication, in 2007, his team showed that due to the extra copy of chromosome 21, the number of molecules produced from this chromosome are increased in the mother’s blood plasma if she is carrying a baby with Down syndrome, and a simple blood test could diagnose it, yet, not only Down’s Syndrome but a range of diseases including cancer.
Then in 2011, with the introduction of new DNA sequencing technology, Dr Lo launched his non-invasive prenatal blood test for Down syndrome, and today, the test is available in more than 90 countries, and more than two million pregnant women have been tested, but with a caveat that it wouldn’t be used for sex selection which is common among clients who come from China.
The Secrets In a Mother’s Blood and Urine
The secrets held by just a few drops of blood are almost limitless, and makes such things as screening an unborn baby for various disorders and gene defects — including the breast cancer gene BRCA1 — a possibility for the future. At present though, the hugely expensive cost means that such tests are not being performed.
Today, Dr Lo is instead working on a blood test for adults, that can detect liver, nose and throat cancer at stages so early they would be invisible to existing screening methods; and his next focus is on DNA testing using a mother’s urine!
Why urine? After a woman delivers a baby, two hours later, the foetal DNA is gone from her bloodstream, and is excreted in her urine. And this may well provide another window into the future health of mother and child, he concludes.
