specialists in
DNA testing
Accredited Test Laboratory
01603 358161
Anglia  DNA Services
Accredited by the UK Accreditation Service to the ISO 17025 international Standard for paternity, maternity, family relationship and sibling testing.
Accredited by the Ministry of Justice to carry out parentage tests directed by the civil courts in England and Wales under Section 20 of the Family Law Reform Act 1969.
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Accredited to:
ISO/IEC 17025:2005

Sibling DNA Test (Kinship Testing)

Sibling testing or Kinship Testing is part of our range of Family Relationship Testing Services. Sibling DNA testing is used to establish whether two or more individuals share both biological parents (full siblings), or whether they share just one biological parent (half siblings) or whether they share neither parent (unrelated), i.e. whether they are full brothers or sisters,half brothers or sisters or are unrelated.

  • 50% of an individual’s DNA is inherited from their biological mother and 50% from their biological father. Each parent has two copies of the 23 chromosomes, so there is a 50% chance that they will randomly pass on a particular chromosome to their children.
  • It is pure chance which combinations of DNA you inherit from your mother and father. When siblings inherit DNA from the same father and/or mother there are ‘similarities’ that can be traced.
  • If two siblings share the same mother and father, theoretically they should share 50% of their mother's chromosomes, and 50% of their father's chromosomes.
  • During a Sibling Test, a number of markers (15 loci) on different chromosomes are examined and compared. If two people are full siblings, approximately 50% of the DNA which is examined should be shared. If two people are half siblings, 25% of their DNA should be shared.
  • Calculations are then made using the ‘likelihood ratio’ to produce a ‘Full Sib Index’ (FSI), ‘Half Sib Index’ (HSI) and ‘Unrelated Index’ (UI). These figures are based on how many pieces of DNA (alleles) at each of the 15 loci are shared between the individuals being tested, and how likely it is that these alleles would be seen if we were to test members of the general population with the same ethnic origin as the people participating in the Sibling Test.


It is important to note that in some cases, test results for the family relationships above will be inconclusive. Inconclusive results occur when the genetic information shared between the potential siblings/relatives is common to that shared by the general population. In these circumstances there is insufficient genetic evidence unique to the individuals being tested to establish the relationship between them.
It is not possible to predict the outcome of one of these tests until it is completed, and unfortunately because of the work involved we are unable to refund clients who receive an inconclusive result.

How to Order a Legal DNA Test

  • Download an Order Form. Alternatively call 01603 358 161 or contact us
  • Complete the form with as much detail as possible
  • Your case will be assigned to a member of our Client services team who will arrange and coordinate sampling appointments on your behalf, saving your valuable time. 
Contact us by email or call: 01603 358161

Price Guide for DNA Sibling / Kinship Tests

Legal Test Service: £399 (for 3 persons)
Additional Persons at: £110

Prices above exclude VAT

Anglia DNA Scientists

Anglia DNA