X Chromosome Tests

Posted on | March 16, 2011 | 1 Comment

The X chromosome test is the ideal test if you are two or more females who wish to know if you have the same dad. The test gives a very accurate result.

The X test, as the X chromosome test is sometimes called, is what you can opt for in order

to establish paternity when the father is unavailable. Yes, ideally, the first choice to consider is a paternity DNA test but in some cases the alleged father might not be available and in this case, it would not be possible to get his DNA sample. A range of relationship DNA tests are available to help solve just about any questions about familial relationships- the X chromosome test is one of them and falls under sibling DNA tests.

Conditions for an X chromosome test

• If female siblings have the same biological mother and want to know if they have the same father they can do and X chromosome test – however, in this case, the mother’s sample is essential and the test cannot be done without it.
• If the females involved have different mothers then it is possible to go ahead with the test even without the mother’s sample.

X Chromosome test results

This test is extremely accurate- a positive and conclusive result means a complete match between the X chromosome profiles of the females involved. In some instances genetic mutations can mean 1 or 2 genetic markers will be mismatched between the genetic profiles; in cases of just 1-2 markers, the result will be inconclusive- it is not possible to say that the females share the same dad but neither to exclude the possibility.

3 or more mismatched markers are a clear exclusion. We can conclude by saying that the X chromosome test is highly accurate and reliable. Genetic mutations on the X chromosome are rare.

Amelogenin Sex gene and Paternity DNA testing

Posted on | February 17, 2011 | 1 Comment

Paternity testing is definitely the most reliable means of ascertaining paternity up-to-date. Testing the amelogenin sex gene has now become an important part of the test and few labs carry out paternity tests without ensuring that they also test this gene.

A paternity test typically includes the DNA sample of the alleged father, the mother and the child. Paternity testing is very accurate and can be done even without the mother’s sample, albeit it with slightly less accuracy. A paternity test done with the mother’s DNA samples will show a probability of paternity higher than 99.99%- this clearly shows the tested father is the true father of the child. If the mother is not included, then the percentage is slightly lower: 99.9%.

When samples are being processed in the lab, scientists want to be sure that they are testing the correct sample. They cannot always rely on clients submitting samples being thorough and careful and thus they need to test the sex of all DNA samples to make sure that they are actually testing the father’s DNA samples, the child’s or mother’s. Your result will show an XX chromosome for the mother, an XY chromosome for the alleged father and the child/children’s chromosomes represented by XX or XY depending on the gender.

Why test amelogenin gene for a paternity test?

People doing the test can make mistake. They may place swabs in the wrong envelopes or mislabel them. One may, for example, accidentally or on purpose, place the mother’s swabs in an envelope and label this envelope as belonging to the alleged father. Testing this gene can also be used in genetic identification in forensic cases. A corpse can be identified as male or female depending on the amelogenin sex gene.

The amelogenin sex gene is found on both the X and the Y chromosome. Males have XY chromosome pairs and females have XX chromosome pairs.

How can sex be determined if the amelogenin sex gene is found on both chromosomes?

DNA is analyzed through a process known as PCR (polymerase chain reaction). When samples are tested for the amelogenin sex gene, the X and Y chromosome will show different peaks for this gene which make it easy to distinguish between male and female samples.

DNA Paternity testing is accurate and reliable. Any serious lab will test the amelogenin sex gene so as to maintain high standards.

DNA Testing

Posted on | January 11, 2011 | 1 Comment

Here we have just a few pointers regarding DNA testing and some misconceptions which are really commonplace. “DNA” is very much a word that today falls in everyone’s vocabulary bank and who has not read or heard some article about DNA testing in the news; some celebrity who was caught in a paternity dispute and had to have a paternity DNA test to sort it out.

Is our DNA really unique?

Well this is quite a myth. Your DNA compared to the first random person of your same ethnic group is give or take exactly the same, save around 2% of the total DNA which is actually different. In terms of the functions all our DNA is responsible for well a lot of our DNA is associated with no known function and appears to do very little if even anything- this is referred to as junk DNA.

For DNA testing, we are only interested in that 2% of our DNA which differs from one individual to the next. It is much more complicated than that because the regions taken are much more specific. Only identical twins have the exact same DNA profile- if two identical twins are the alleged fathers of a child it would be impossible to know which of the two is the biological father of the child.

So a biological father and child will only share certain genes but the vast bulk of their DNA will not be different from other people. However, the genes, or rather loci, tested in a paternity (test de paternitate) test leave no doubts as to whether a man is the biological dad or a child or not.

In all other cases, DNA testing for paternity is conclusive and reliable.

The DNA Test

Posted on | November 30, 2010 | No Comments

The DNA Test: DNA (deoxyribonucleic acid) is the genetic blueprint that determines a person’s biological characteristics. DNA is located in the cell of the human body. Upon conception, a child inherits one half of its DNA from its mother and one half from its father. This unique combination of DNA will match that of the biological parents of the child.

A DNA test does not involve analysis of the entire DNA in our body. When doing a paternity test, laboratory analysts will analyze only very specific locations on the DNA molecule. These locations are referred to as genetic loci and analysis of just a few of these loci and the consequent comparison of them between alleged father and child can easily give you the result of the paternity DNA test(test de paternitate).

The DNA Test: How is it done?

For the test to take place, cheek cells are removed with a swab from the mouth of the mother, the child and the alleged father. In the laboratory, these cells are removed from the swab and tested. When a child’s DNA does not match that of the alleged father, he is excluded 100% as the biological father of the child. When the child’s DNA does match that of the alleged father, this means that the alleged father is the biological father of the child.

If for example, the two alleged fathers in a paternity test are brothers and thus have extremely similar genetic makeup (although it is possible for the genetic similarity between full sibling to vary and thus, they may have genetic profiles which are almost the same or perhaps entirely different) paternity DNA testing can still distinguish which of the two men is the biological father of a child. The real father will always have a probability inclusion of paternity of 99.9% or higher; the brother will have a very high probability of paternity of let’s say 98% but this percentage is not high enough for him to be the biological father of the child- he is clearly the uncle of the child.

The DNA test, whether for paternity or to determine the existence of relationships between people is highly accurate and reliable. However, the DNA test becomes less accurate as the relationship between people becomes more distant (second and third cousins for example)

Sibling DNA testing

Posted on | November 1, 2010 | 1 Comment

Sibling DNA testing is a means of determining what the nature of the relationship between siblings is. Siblings can have both parents in common, meaning they are full siblings; one parent in common, which would make them half siblings or perhaps no parents in common would mean they are not siblings at all.

Sibling DNA: How much DNA do they really share?

It is hard to provide an accurate percentage of shared DNA that applies to siblings; however, it is estimated that full sibling (which share both biological parents) will share around 50% of their DNA. There may be instances where full siblings share very little of their DNA or some cases in which they may have 100% of their DNA in common- the latter example is only seen however, with identical twins.

Sibling testing falls under the umbrella of relationship DNA testing. Relationship tests are designed so as to solve diverse familial relationships involving aunts, grandparents, cousins and of course siblings.

The proximity of the genetic relationship between full siblings makes sibling testing quite accurate.

With cousins, for example, things are more complicated should they wish to establish whether they are truly cousins- first cousins only share around 25% of their genetic makeup and this number falls by 1/5 with each successive generation. Half siblings will also share around 25% of their DNA.

How is a sibling DNA test done?

Sibling DNA tests are normally carried out by means of a simple mouth swab which is rubbed inside the mouth to collect cheek cells and saliva. The test is normally used to determine whether siblings share a common parent- usually the father. Since the accuracy of the test is not as high as a paternity DNA test, the first option to consider for any siblings wishing to know whether they have a common father is to do a paternity test- hence, testing directly the alleged father’s DNA sample and comparing this to the DNA of his children.  However, in some cases, the father may not be available for testing and is such cases it is worth doing sibling testing.

Adding any known parent to a sibling test always helps provide a stronger result especially where the sibling test is an X-chromosome test or a full sibling test.

Because sibling DNA testing involves establishing a biological relationship with another person without testing their DNA makes this test, as mentioned above, less accurate.

LeBron Raymone James required to take paternity DNA test

Posted on | September 28, 2010 | No Comments

NBA player, LeBron Raymone James, simply known by his first name, may need to take a paternity test. A lawyer who practices in Washington has come forward claiming to have had an affair with LeBron’s mother in 1984 and that she was left pregnant with LeBron from this affair. He has compiled his case and will present it in court so as to get the paternity DNA test that will prove he is the biological father of LeBron.

LeBron’s alleged father Leicester Bryce Stovell is suing his son for the astounding sum of 4 million $. He has been pressing for the test since 2007 and moreover, claims that LeBron and his mother, Gloria James have concealed that fact that Stovell was the biological father. A paternity test was carried out in 2007 but the result was an exclusion; meaning Stovell was excluded as being the biological father. However, the 55 year old lawyer says he is certain that Gloria cheated so as to alter the results and that both her and LeBron were in agreement on this.

He says that he specifically remembers Gloria informing him when she was pregnant, telling him that he was the father and that she intended naming the child LeBron.  He alleges that Gloria James went as far as to threaten him in order to keep him out of his son’s life and that she has committed fraud in her attempt at knowingly concealing the identity of LeBron’s father.

Gloria James had previously named who she thought was the biological father of the child- Anthony McCelland. However, Frederick Nance, attorney for Gloria James, says that a paternity test had already been carried out and that it excluded McClelland as the father. Stovell will be presenting his own case as a legal practitioner hoping that he will get a court ordered paternity test.

A court ordered paternity test or legal paternity test can be requested by either the mother of the alleged father. Usually people seeking such tests want to solve visitation disputes, have their children get their legal rights and get financial support.

Paternity DNA testing has become a sound legal tool that is now the standard, accepted means to establish who the biological father of a child is. LeBron James is just one of many celebrities who have been involved in such cases. Tiger Woods, Mel Gibson and a host of other have been involved in paternity disputes that have been solved thanks to the accuracy and reliability of DNA paternity testing.

Baby DNA test: Who is the father? Part II

Posted on | September 2, 2010 | 1 Comment

Any person who has had more than one partner and falls pregnant will naturally want to know who the father of the child is. A baby DNA test is one means of establishing with certainty who the daddy of the unborn child is. One can of course choose to wait till after the child is born although it is important to know that this is not necessary as a paternity test can be conclusively carried out while the mother is still pregnant.

How is the Baby DNA testing done?

There are two main methods through which the unborn baby’s DNA can be sampled for a baby DNA test.

Amniocentesis: this is carried out anywhere between week 14 and week 20 of the pregnancy and is normally done as a routine procedure to locate abnormalities in the chromosomes. The procedure is normally done by gynecologists under local anesthetic who will insert a needle into the womb through the abdomen. The fluid extracted will contain loose fetal cells and some of the mother’s cells too. The process is invasive and there could be consequences. Although the chances are minor, they are nevertheless, still there. These include:

• Infection to the amniotic sack due to the needle
• Infections at the point in which needles puncture abdomen
• Fetal trauma
• Early labour
• Serious complications which could lead to miscarriage

Chorionic Villus Sampling (CVS): another method that can be used for establishing paternity before birth is CVS. CVS can be carried out earlier in the pregnancy and the gynecologist enters through the vaginal cervix. Again, the procedure is invasive and there are certain minor risks of infection of inducing miscarriage.
Pre-natal testing comes at a considerable added cost which is needed to cover the medical fees. Moreover, to some, due to the invasive nature of the test, may even be psychologically burdensome. A mother has a given period of time to register a father on the child’s birth certificate which is ample to carry out a paternity test after the child’s birth.

Is it Necessary to do a baby DNA test?

Whether to do this type of test is very much a personal choice and there are a number of considerations involved. Will getting the results which are not desired induce an abortion? This opens up a whole new complex issue. Until a father is not registered in the child’s birth certificate, then the child does not have access to all his or her legal rights.

Pre-natal testing is by far more expensive as you will need to pay the surgeon’s fees and set up appointments etc. Ideally, waiting till the birth of the child is likely the most recommended option as baby DNA tests are still very much at the centre of ethical debates so that many DNA testing companies prefer not to carry them out.

Baby DNA Testing: Who is the Father? Part I

Posted on | July 20, 2010 | No Comments

The Baby DNA test, often refered to as a pre-natal test, is a means of establishing paternity before the birth of the child. However, this test is also a means of seeing whether the unborn child suffers from certain genetic conditions such as Tuner’s syndrome, chromosomal disorders such as Down syndrome or other congenital disorders . The article  focuses on the DNA testing of the unborn child to establish paternity rather than the array of  pre-natal tests which are carried out to chek for illnesses and the general health of the child and mother.

Post-natal versus pre-natal DNA testing

A post natal test is done after the birth of the child, even immediately after birth. For some alleged fathers, perhaps waiting nine months is too long but ideally a post-natal paternity test is the one to go for. Once the child is born all that needs to be done is rub a swab in the baby’s mouth to collect some cheek cells.  A swab from the father and from the mother will also be taken so as to come up with a DNA profile for each. If the DNA profile of the baby and father match, then the father is the biological father of the child.

A baby DNA test carried out before birth absolutely requires the DNA samples of the mother and the father. The crucial importance of the mother’s sample is due to the fact that the prenatal DNA sample will contain a mix of the mother’s cells as well as the child’ and thus, it is crucial for labs to distinguish between the two DNAs so as to provide the correct result.

Pre-natal testing involves two main ways of obtaining DNA samples- the first is known as chorionic villus sampling or CVS and the second one is known as Amniocentesis. Both types of DNA sampling for baby DNA tests are invasive and involve being under local or general anesthetic and will thus need full medical assistance. Given this, there are much higher costs involved as well as certain risks.

Once the DNA samples have been collected, the paternity test can proceed as normal. Baby DNA tests are accurate and reliable although the thought of the medical intervention may not appeal to all mothers.

Tiger Woods: Another Case of a Celebrity Paternity DNA Test?

Posted on | June 21, 2010 | No Comments

Tiger Woods, 36, has allegedly had a number of affairs with different women; according to some sources,  Woods has had 15 different mistresses. Recently, his mistress of two and a half years, Devon James 29, has come forward claiming to have had a son from the golfer.  A paternity DNA test will most likely be indispensable to solving the case and James is already in court trying to get one.

James gave birth to the child she claims to be Woods’ in 2001; this was the time when Wood’s and his wife, the Swedish model Elin Nordegren, where expecting their first child together. James, a porn star by profession, has come forward with Wood’s alleged child, Austin T. James, who is now nine years of age. The golfer’s name made the headlines in 2009 in conjunction to a sex scandal involving another mistress, Theresa Rogers. Rogers too claimed to have Wood’s child and the two decided on an out-of-court settlement of 2 million US dollars.

James is now 29 years old and met Woods when she was just 19. Woods is rumored to have had at least 15 women in his life and many have questioned whether James’ claim is actually true- why would she have waited so long to come forward? Nine years seems an awfully long time.

Woods had in 2009, under media pressure and mounting allegations by women claiming to have had affairs with him, made a public statement which was not only an apology to his wife and family but in which he also admitted to his affairs with women.

In the case involving Devon James, there has not as yet been any paternity DNA test to establish the truth- is Tiger Woods Really the boy’s father? If the test establishes that Woods is the boy’s father, the golfer will have to take on all his parental responsibilities as dictated by the law. James Devon would have grounds to claim nine years of retroactive payments and of course, Woods’son, Austin T. James would be entitled to child support from his millionaire golfer father.

How is a paternity test done?

The procedure for paternity tests is pretty much standard. The test is normally done using oral swabs which a rubbed within the mouth to collect the DNA found in cheek cells which gets stuck to the swab. The DNA analysts will extract a DNA profile from the alleged father, child and mother (the mother’s sample is not indispensable to the test but is recommended in cases where the mother is available). If the genetic markers between the father and the child match then the alleged father is the biological father. In such cases, the inclusion percentage for paternity is 99.99% or higher. If the genetic markers between the father and the child do not match, then the alleged father is not the biological father.

There have been numerous celebrities making the headlines seeking to clarify their paternity disputes by doing paternity DNA tests; these include Mel B and her affair with Eddie Murphy as well as the recent person who came forward claiming to be Oprah Winfrey’s father. The case involving Tiger Woods will likely be solved thanks to paternity DNA testing and a judge can issue a court order for a test.

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