Information regarding kinship investigations
Oslo University Hospital offers DNA tests that are highly suitable for establishing or excluding paternity, maternity, or sibling relationships, but are often less well suited in order to support or disprove more distant kinship relations.
At the Section for Forensic Genetics – Kinship and Identity, analyses are based on 23–46 so-called STR loci (short tandem repeat DNA sequences) located on the autosomes (non-sex chromosomes). Such analyses generate a DNA profile that is highly suitable for establishing or excluding paternity, maternity, or sibling relationships. However, they are generally less informative for substantiating or excluding more distant kinship relationships.
In certain cases, it may also be difficult to distinguish between very closely related relationships. For example, differentiating between full siblings and half-siblings who share the same mother but may or may not share the same father can be challenging. In such cases, analysis of the mother is usually required to obtain a conclusive assessment of the full sibling versus half-sibling relationship.
As a general principle for all assignments undertaken by the section, the inclusion of a greater number of close and well-documented relatives increases the likelihood of obtaining a reliable conclusion regarding the presence or absence of a biological relationship where there is uncertainty.
Additional analyses of the sex chromosomes (X and Y chromosomes) may, in some cases, provide supplementary information.
The Y chromosome is typically inherited unchanged from father to son across generations. Consequently, Y-chromosomal DNA profiles can be informative when assessing whether two males are related through their paternal line or share a common male ancestor.
X-chromosomal DNA profiles may also be informative. In females with the same father, the paternally inherited X chromosome will normally be identical. If they share the same mother, analysis of the mother is likewise of significant importance for evaluating the strength of the genetic evidence.
If the DNA analysis performed by the section does not yield a conclusive result, other DNA analysis methods—such as SNP-based analyses (single nucleotide polymorphisms)—may provide additional insight. The Section for Forensic Genetics – Kinship and Identity does not currently offer such analyses.
However, several external providers offer these types of tests, including Family Tree DNA, MyHeritage, and 23andMe. These are provided as examples only and do not constitute recommendations from our side.
It is important to note that such companies operate under different policies and procedures regarding privacy, data use, and data sharing than Oslo University Hospital. This should be carefully considered before submitting samples for analysis. For example, these services often involve comparing an individual’s genetic data against data stored in the company’s databases. As a result, participants may receive information about potential relatives identified in the database, either at the time of testing or at a later date.