Dna testing

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Prenatal Paternity Test

• Chorionic Villus Sampling (CVS)

The CVS procedure is performed during the 10th and 13th week of pregnancy. This procedure involves the removal of a small amount of placental tissue for testing.

• Amniocentitis

The Amniocentitis procedure is performed during the 14th and 24th week of pregnancy. Guided by ultrasound, the OB-GYN will use a long needle to collect Amnio fluid samples through the abdomen.

Prenatal Paternity Test

• Prenatal DNA paternity testing produces

conclusive results with 0% probability of

paternity if the alleged father is not biologically

related to the child or with greater than 99.9%

probability of paternity if the alleged father is the

biological father of the tested child.

Paternity DNA Test

• DNA paternity testing determines the biological father-child relationship between a man and a child. Every individual’s DNA or genetic fingerprint is unique except for identical twins.

• The DNA paternity test compares the DNA fingerprints between the tested man and child to determine if the child inherits half of his/her DNA from the alleged father.

• Mother’s participation is optional although her participation helps to exclude half of the child’s DNA fingerprint inherited from her, making the data analysis easier.

Maternity DNA Test

• DNA maternity testing determines the biological mother-child relationship.

• Applications for Maternity DNA Test

1. Immigration DNA Test

2. Adoption

3. Surrogacy

Grandparentage DNA Test

• Grandparetnage DNA testing determines if an individual (or a couple) and a child are biologically related as grandparent(s) and grandchild. It is often used to determine paternity indirectly in cases where the alleged father is deceased or unavailable for testing.

• Since we all inherit half of our DNA from our biological father and half from our biological mother, we inherit a quarter of our DNA from each of our biological grandparents.

Siblingship DNA Test

• In the siblingship DNA test, two individuals are tested to determine whether they share one or both of their biological parents.

• Full siblings share both of their biological parents and half siblings share one of their biological parents.

Other DNA Tests

• Y-STR DNA Test

This DNA test determines if two males are paternally related. The Y-Chromosome is passed from father to son relatively unchanged through many generations. Males sharing the same male ancestor have the same or very similar Y-STR DNA profile.

• mt DNA Test

This DNA test determines if two individuals are maternally related. The mtDNA is passed from mother to children relatively unchanged through many generations. Individuals sharing the same female ancestor have the same or very similar mtDNA sequences.

Other DNA Tests

• Twin Zygosity DNA Test

The twin zygosity DNA test is used to determine if twins are identical or fraternal. Every person’s DNA is unique except for identical twins. If the twins share the exact same DNA profiles, they are identical. If they don’t share the exact same DNA profiles, they are fraternal.

This DNA test is used for personal curiosity or to help solve health problems when a twin needs an organ or tissue donor. The identical twin is a perfect choice as a donor in these medical circumstances.

Other DNA Tests

• Avuncular DNA Test

The avuncular (aunt/uncle) DNA test is used to determine relatedness between a child and his/her uncle/aunt when the biological parent that links the relationship is deceased or unavailable for testing. Participation of the child’s other parent is strongly encouraged for more conclusive results.

Genetic Reconstruction DNA Test

• A genetic (family) reconstruction DNA test determines biological family ties between a child and her paternal or maternal relatives when the alleged parent is deceased or unavailable for testing. It is typically used as an indirect way to determine paternity or maternity.

• In the genetic reconstruction DNA test, the child’s DNA profile is compared with the DNA profiles of at least two of the alleged parent’s close relatives. Since everyone inherits half of the genetic materials (DNA) from the biological father and half from the biological mother, close relatives share a significant portion of their DNA profiles.

Forensic DNA Test

• The forensic DNA testing technology has been applied to identify suspects and victims in violent crimes, and discover identities of victims of natural or plotted disasters.

• By analyzing and comparing reference samples and biological materials such as blood, tissues, and finger nails left behind at a crime scene, forensic DNA scientists are able to link suspects and victims to a specific crime.

DNA Typing and Banking

• DNA typing and banking services provide individuals with their DNA profile and preserve their DNA specimen for future genetic testing when needed. Each individual’s DNA profile (or genetic fingerprint) is a permanent means of identification.

• Universal Genetics provides DNA banking service to store DNA in a medically secure facility that maintains the viability of DNA for future testing. The preserved DNA can be used for genetic disease diagnosis, ancestral lineage or paternity testing to solve legal issues such as inheritance claims when the tested party is no longer available for testing.

DNA Test Results Interpretation

• It is routinely test 16 genetic markers that are known for being highly differential between individuals. A DNA paternity test compares the sizes of these markers between an alleged father and a child.

• Each DNA marker contains two alleles, one inherited from the biological mother and the other from the biological father. The DNA test finds out whether there is at least one match out of the two alleles on the same marker from the alleged parent’s and child’s DNA.

DNA Test Results Interpretation

DNA Marker Mother Child Alleged Father

D21S11 28, 30 28, 31 29, 31

D7S820 9, 10 10, 11 11, 12

TH01 14, 15 14, 16 15, 16

D13S317 7, 8 7, 9 8, 9

D19S433 14, 16.2 14, 15 15, 17

DNA Test Results Interpretation

• The partial results indicate that the child and the alleged father’s DNA match among these five markers.

• Each marker is assigned with a Paternity Index (PI), which is a statistical measure of how powerfully a match at a particular marker indicates paternity.

• The PI of each marker is multiplied with each other to generate the Combined Paternity Index (CPI), which indicates the overall probability of an individual being the biological father of the tested child relative to any random man from the entire population of the same race.

• The CPI is then converted into a Probability of Paternity showing the degree of relatedness between the alleged father and child.