Scientists Map Entire DNA of Human Fetus

December 10, 2010

Courtesy: foxnews.com

Parents may soon be able to find out if their unborn child is prone to any inherited diseases, researchers said on Thursday, after developing a non-invasive technique to draw the entire gene map of the human fetus.

By analyzing a sample of the mother’s blood, which contains DNA from the fetus, scientists in Hong Kong and the United States were able to identify all the DNA strands that belong to the child and piece them together.

“Before this work, people only could look for one disease at one time but now you can construct a screen for a number of diseases which are prevalent in any particular population,” said lead author Dennis Lo, professor of medicine from the Chinese University in Hong Kong.

The research team’s breakthrough was discovering that the mother’s plasma holds the entire fetal genome. Previously, only part of the baby’s DNA was thought to be in the mother’s blood.

“Now that we know (the) entire fetal genome is in there, you can look for any disease that is genetically inherited.”

The study, published in the journal Science Translational Medicine on Thursday, recruited a couple undergoing prenatal diagnosis for a hereditary blood disorder, beta-thalassemia.
“In the mother’s blood, 90 percent of the DNA is her own … and 10 percent is the baby’s. Half of the fetal genome is from father and half from mother,” Lo said.

Lo described the process as akin to putting together a jigsaw puzzle with millions of pieces — only in this case, 10 times as many pieces from a much larger jigsaw were mixed in with it too.

“The whole genome is fragmented into millions of pieces and by this exercise, we assemble it back,” Lo said.
“It’s like assembling a jigsaw puzzle with millions of pieces. But to make it more challenging, you mix in 10 times (the number of pieces) from another jigsaw puzzle, that’s the mother’s own DNA. And you are trying to assemble the child’s.”

Experts who were not involved in the study called for caution.

“It is too early to apply the technology widely as we are not yet able to interpret many of the results that can be generated accurately,” said Christine Patch, chair of the British Society for Human Genetics. “We do not randomly test pregnancies for a long list of … conditions that may only manifest in adult life on the basis that individuals may not want to know that information when they are older.”

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Chinese Study Suggests New Way to Test for Genetic Diseases

December 10, 2010

Courtesy: health.usnews.com

A new test that requires only a tiny sample of a mother’s blood to scan the genome of a fetus may offer a safer alternative to current methods of prenatal screening for genetic diseases, a new study suggests.

Currently, a sample of fetal tissue is collected using invasive procedures such as amniocentesis or chorionic villus sampling, both of which pose a small but definite risk to the fetus.

But, Chinese researchers found that fetal DNA floating in the mother’s blood contains the entire fetal genome and can reveal a number of genetic and chromosomal disorders in the fetus.

They used the method on a couple undergoing prenatal diagnosis for a type of genetic anemia called beta-thalassemia. The results showed that the fetus had inherited the beta-thalassemia mutation from the father and a normal gene from the mother, meaning the fetus was a carrier of the disease.

The study is published in the Dec. 8 issue of Science Translational Medicine.


Is a Thalassemia test too much to ask?

October 10, 2010

Courtesy: Tribune.com.pk

As I typed the list of thalassemia centers all over Pakistan, my cellphone started ringing and diverted my attention. On inquiring who was calling, I heard a sad and depressed voice on the other end. A father’s voice.

I usually get calls but there was something special about this particular one. The guy got married around two years ago to the love of his life (who was his cousin). Now they have a one-year-old baby… and that baby is a thalassemia major.

According to him, no one in their family had this disease, but both of them were thalassemia minor and they didn’t know about it before.

He asked me “Why did it happen to us?”

I couldn’t stop myself from asking him “In this advanced age, why didn’t you know about a simple blood test?”

Because of my previously written articles people think I amagainst cousin marriages, though I am not. I just wish for people to go through a simple blood test. If every existing thing has a reason behind it, then the thalassemia test has a reason too!

After talking to the father for more than 30 minutes and telling him what he should do now, what are the options etc, I ended the call with the realisation that there is still a huge section of our population that lacks awareness regarding this issue. I believe the media has a strong influence on people and they should come forward and take part in raising this awareness. I bet if a TV ad ran on every single news channel for just a short period of time, it would save several lives.

Once again I will state I am not against cousin marriages, but if you are going to get married please get yourself tested!

A simple blood test can save your next generation… is it too much to ask?


Apollo Hospitals introduces coagulation screening test

September 7, 2010

Courtesy: thefinancialexpress-bd.com

Apollo Hospitals, Dhaka has introduced a coagulation screening test in single blood sample in its lab medicine department, according to a press release.

Coagulation screening test provides precise diagnosis of any abnormality of blood coagulation as in hemophilia, thalassemia, blood malignancy, other malignancy or any genetic disorder.

This screening consists of a set of seven tests like Bleeding Time (BT), Clotting Time (CT), Platelet count, Prothrombin Time (PT), Activated Partial Thromboplastin Time (APTT), Thrombin Time (TT) and Fibrinogen assay in a single blood sample collection.

The report will be delivered same day after 5:00 pm if sample is received within 12:00 noon, if later then it will be delivered next day after 10:00 am, the release added.


‘Drug shortage alone can’t cause premature Thalassaemia deaths’

August 15, 2010

Thalaessaemia patients can’t die prematurely just because they don’t have drugs. There are other factors to consider as well”.
So says Dr R. Mudiyanse, Consultant Paediatrician and lecturer at the University of Peradeniya.
In a frank interview with The Nation, Dr Mudiyanse, who admits that he himself is a thalaessaemia carrier said, “To say that temporary drug shortages can kill a thalassaemia patient is an emotional and irresponsible statement. You need to understand all sides of this disease, to make a fair judgement. Let me explain why these patients need drugs. The reason is that regular blood transfusions are essential for thalassemia patients, because unlike in normal persons where the red cells live upto 120 days, the red cells in thalessaemia patients are broken down in a much shorter time. Then they become anaemic, and so need blood transfusions. Those with severe thalassemia need to have blood transfusions every month, for life. With each pint of blood given them, there is iron accumulation. This is because blood in our body contains a great deal of iron. This iron when accumulated over a long period can become toxic to the body as it releases electrons that can damage cell membranes in the body. In the heart it can cause heart failure, in the pancreas it can lead to diabetes, in the liver result in cirrhosis, the pituitary glands resulting in stunting, in the gonads (ovary) it can prevent them from attaining maturity. It is to avoid these complications that they need iron removal drugs.”

What are these drugs? Are they available in the hospitals?
“There are 3 types of drugs which we give our patients. One is an injection taken once a day and which requires a 12 hour infusion. The other two are tablets, taken 3 times a day and once a day respectively. Whatever the iron that is accumulating in their cells due to a blood transfusion can be removed only by taking these drugs for 25 days every month. This has to be repeated each month after every blood transfusion.”

So if they don’t have the drugs will it shorten their lifespan?
“Patients can’t die overnight just because they don’t have a certain drug. Iron accumulation in the cells is a long process. But if they fail to take the drugs or have a blood transfusion on a long-term period, it can lead to premature death”.

He reiterated that for patients to lead a full life they required to take their blood transfusions and drugs on a regular basis. “If they take their blood transfusions regularly they can live upto 20 years, even without drugs. But our patients don’t do this. That is why most patients in Sri Lanka die before 20 years. Of course, it is not easy to have a blood transfusion every month, but they must comply with this requirement. So non-compliance to this basic requirement is the main cause for them dying prematurely”.

And patients who did comply with these requirements?
“They can live upto 50 or 60 years and above and lead normal lives, get married, become lawyers, engineers, doctors etc”.
He admitted, however, that administration of sub quality drugs for a long period could have adverse effects and lead to early death.
Currently Sri Lanka has an estimated 4% population with thalassemia. There are around 100 new patients born every month and an estimated 2,000 patients every year.
Each year the state is required to spend between 100,000 to 300,000 on a patient. This puts an unbearable burden on the government as all the drugs and transfusions are given free. What is important thus is prevention of the disease – through education and awareness raising”, he stressed.

Dismissing the popular belief that consanguinity or first cousin marriages are the underlying cause, he said, “While consanguinity is a risk factor for having thalassaemia babies, it is not the only cause. The main cause is conception between two carriers, which carries a high risk for resulting in them having a thalassaemia baby. So conception between two carriers (i.e. where the mother and father are both carriers) must be avoided at all costs. If a person knows he is a carrier, and wants to get married, he should get his future spouse to be tested to see if he/she is a carrier or not. If, on the other hand, you are not a carrier, then you needn’t worry about checking to see if your prospective bride or bridegroom is a carrier, as both should be carriers to produce a thalassaemia baby.”

However, he also pointed out, “In a conception between two carriers usually only about 25% of babies get thalassaemia. According to our statistics, we can assume that every year, we have about 400 conceptions between two carriers resulting in around a 100 births of thalassaemia babies. Hence we can assume there are about 200 such high risk marriages between two carriers happening every year. This is the group we should target so as to prevent these marriages taking place. And for this, I reiterate, testing the blood of your future partner is important if you are a carrier, to rule out that the latter is not a carrier as well”.

Do you recommend that testing be mandatory?
No. It has to be a responsible decision. My message is: “If you are a carrier then don’t take the risk of marrying another carrier. The only way to know this is by getting your would be partners for life tested before marriage”.
The Nation also spoke to Professor Priyani Soysa, Consultant Paediatrician, who was among the pioneers to have raised awareness on Thalassaemia in the late 50’s while working at the Kurunegala hospital. “It was the late Professor C.C. de Silva who observed the disease in the 1940’s. Then when I had many babies and older patients coming to the hospital for treatment, I began an awareness raising programme, to discourage consanguinity which I found was one of the leading causes for the disease
Not all first cousins marriages result in thalassaemica babies. But those who have minor thalaessemia which is a recessive disorder can result in major disorder when blood cousins marry.”
She too says that testing should not be mandatory as it will be infringing on Human Rights.
“On the other hand, people must be made aware and educated on the disease, so that one carrier will not marry another carrier of the disease”.


UAE Genetic Diseases Association runs series of Thalassemia screening campaigns

May 26, 2010

Courtesy by: bi-me.com

UAE Genetic Disease Association (UAEGDA), the sole non-profit genetic organization in the UAE, has begun a month-long screening campaign to bring attention to the presence of thalassemia in the UAE following the commemoration of World Thalassemia Day earlier this month.

According to the Genetic and Thalassemia Centre in Dubai, one in 12 persons in the UAE is said to be a carrier of the disease.

The latest UAEGDA campaign is touring locations throughout the UAE with over 500 volunteers from various institutions assisting in the effort. Participants are working under the mission of educating the population about common genetic disorders (such as Thalassemia, Sickle Cell Anemia, G6PD Deficiency & Diabetes) and informing them about the free screening and counselling services provided by the UAEGDA. Different venues will be targeted throughout the month of May including Deira City Centre, 11 different Emarat and ADNOC fuel stations across the UAE, and various colleges and corporate houses.

Nearly 5,000 individuals were tested for the disease in the last year, according to UAEGDA officials, and an expansion of the group’s capacity has attracted partners throughout the country, including groups like the UAE Marriage Fund—a partner in UAEGDA’s current campaign.

The benefits of screening tests lay not only on an early detection of the disorder, but also preventing the birth of children born with thalassemia major. As in the case of all hereditary recessive diseases, there is a 25% chance for the child of thalassemia-carrier parents to become affected, another 50% chance of which will be carriers, while the rest go on seemingly unaffected.

“Thalassemia is a major public health issue in the UAE, which affects so many families at social, medical, financial and psychological levels,” says Dr. Maryam Matar, Founder & Chairman of UAEGDA. “Blood screenings campaigns in general are the best way to help reduce the presence of hereditary diseases in the country. Certain diseases like thalassemia and diabetes have especially high prevalence in the UAE, and this is the first step in identifying a problem that could extend for generations to come.”

A great deal of scientific data has in fact been documented to show trends of selected genetic disorders in UAE communities, and it is the mission of UAEGDA to make the country free from births of children born with thalassemia by 2012.


Call To Adolescent Males To Undergo Thalassaemia Screening

May 15, 2010

Courtesy by: bernama.com

KUALA LUMPUR, May 8 (Bernama) — Adolescents, especially males have been advised to undergo screening for thalassaemia, an inherited blood disorders that affect the body’s ability to create red blood cells.

Health Minister Datuk Seri Liow Tiong Lai said awareness of the disease among males was still low as they accounted for only 20 per cent of 206,390 people who underwent screening last year.

He said 29,326 people took the thalassaemia test in 2008 and the figure grew to 206,390 last year.

“I appeal and encourage more young people, especially males to take the test as it only need to be done once in a lifetime,” he said when opening the International Thalassemia Day celebration with the theme “Thalassemia: Knowledge is Strength” here on Saturday.

His text of speech was read by Health deputy director-general Datuk Dr Hasan Abdul Rahman.

Liow said adolescence and early adulthood was the most suitable stage to undergo the test as intervention counselling was more effective at a young age.

He said a thalassemia prevention programme can be done at several selected hospitals, especially those that provide thalassaemia treatment as well as 345 health clinics equipped with laboratory equipments to carry out thalassaemia gene carriers screening.

According to the National Thalassaemia Register, to date 4,768 thalassaemia patients have been registered compared to about 2,500 people in 2004.

Liow said at least one out of 20 people in the country was a thalassemia carrier or approximately 600,000 per a million population.

Patients suffering from thalassemia are required regular blood transfusions. Thalassaemia carriers do not show any signs of abnormalities or health problems.


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