Family studies
Results with up to 99.999999% reliability
Unlike paternity or maternity studies, studies of other relationships conducted to confirm relationships between siblings, grandparents-grandchildren, uncle-nephew, etc. require more complex tests.
The genetic study to be performed will be determined based on the relationship you want to confirm (siblings with the same father, same mother, or other relationships such as grandparents/grandchildren, cousins, etc.), so it will be important to define the relationship you want to validate during the purchase process.
How do I initiate a family genetic study process?
It is not necessary to involve a judge or lawyer to initiate a family genetic study, and any adult – father, mother, descendant, or family member – can initiate it as long as they have samples, or can access samples, from all individuals involved in the study.
The key in this case is to determine the relationship you want to confirm or rule out, whether it’s between siblings, second-degree relatives, ancestors, or descendants. Depending on the relationship you want to study, it will be necessary to obtain samples from the individuals involved in that particular relationship. However, the general process always follows the same procedure:
The steps to follow are:
1
Purchase a Family Relationship Study Kit
The kit can be purchased directly on our website. The basic kit includes sample collection from two individuals, although you can incorporate as many people into the family relationship study as you want to analyze. You can choose between two types of genetic studies: informative or legally valid.
While it is not necessary to identify the participants at the time of purchase, and they will be referred to as Sample 1, Sample 2, Sample 3, and so on until all the participants in the study are accounted for, you must indicate the family relationship you want to confirm between them to determine the type of genetic study our technicians should perform with the samples.
In the case of desiring a legally valid study, whose results will have the status of evidence in a potential legal proceeding, all individuals donating biological samples must identify themselves with a document (ID card, passport…) and sign the sample collection document, which will be taken by professionals in a laboratory. This will follow a special procedure to ensure the chain of custody of the samples throughout the process.
2
Collecting the samples
If you wish to conduct a purely informational genetic study to clarify any doubts about your relationship with another family member, sample collection can be carried out in the privacy of your home very simply, following the instructions in the kit you will receive. The kit will arrive in an anonymous and discreet package to the address you have provided. You can collect the samples by swabbing the inside of the mouth or providing genetic material, such as a saliva-impregnated tissue or blood, a hair follicle, or similar.
However, if you want the results obtained from the genetic profile to have legal validity in a potential legal proceeding, sample collection must be done by professionals in a laboratory, and it is necessary for all sample donors to be present and identified to ensure the validity, origin, and chain of custody of the samples throughout the process. Once you have completed the purchase process on our website, one of our team members will contact you to arrange a date on which all individuals involved must go to the laboratory. We will provide you with different laboratory options so you can choose the most convenient one for you.
Please remember that if any of the donors are minors, it will be necessary to have the signed authorization from their legal guardian for them to participate in the process.
3
Sending the samples to our laboratory
To facilitate informative family studies, all kits are sent directly to your home. These kits include a secure box and a prepaid envelope in which you can place the samples and send them by regular mail to our laboratory.
In the case of studies with legal validity, where samples must be taken by professionals in a laboratory, the envelopes go through an additional process. Each transfer is carefully documented, including the identification of all professionals involved, ensuring the integrity of the samples. The laboratory will be responsible for sending them through a secure shipping circuit to our own laboratory.
4
Creation of genetic profiles from the samples
Once the samples are received in our laboratory, they will be anonymized with a unique code, and the genetic profile will be obtained.
The analysis will determine, with up to 99.999999% reliability, the family relationship between the individuals participating in the study.
5
Drafting and sending the conclusion report
Once the analysis is completed, we will issue a report with the conclusions, which will be sent in electronic format via email to the addresses provided in the purchase process. The final format will be like this for informative studies, or like this, with donor identification, for studies with legal validity.
The estimated time from the receipt of the samples in the laboratory to the sending of the report is 5 business days.
Why trust Citogen for your kinship studies?
The most reliable answer to many of the questions that keep us up at night lies in our genes, and at Citogen, we have specialized in DNA processing, extraction, and analysis since 1998. With over 1000 paternity tests conducted annually and numerous cases resolved in the courts each year, we have a proven track record.
We are pioneers in clinical and forensic genetics in Spain, widely recognized internationally, and equipped with the most advanced and modern technologies and facilities in the market, allowing anyone to benefit from the advances made over the years in the fields of genetics, genomics, and transcriptomics, all at very affordable prices.
Our laboratory complies with the National Commission for the Forensic Use of DNA (CNUFADN) Agreement under the Spanish Ministry of Justice. Additionally, we hold UNE-EN ISO/IEC 17025 accreditation and are members of the International Society for Forensic Genetics (ISFG).



Frequently asked questions
- What is the difference between a family study and a paternity/maternity study?
A family study encompasses a broader range of possible relationships, such as grandmother-granddaughter, brother-sister, grandfather-uncle-nephew, and many more possibilities depending on the number of participants.
- Is a test like this valid in a paternity trial?
Family studies, as long as they have legal validity, can be used as evidence in a trial, not specifically for paternity.
- What does a family study report look like?
Here is an example of a family study report, in this case, a sibling study.
- How long will it take to receive my report with the results?
The estimated time from the receipt of the samples in the laboratory to the sending of the report is 5 business days.
- Will I have a laboratory near my home for taking samples with legal validity?
Once the purchase of the kit for the legal validity study is completed, a member of our team will contact you within a maximum of 2 business days to provide you with the address of the nearest collaborating laboratory based on your postal code and initiate the process to schedule your appointment.
- What type of samples are valid for conducting a kinship study?
There is a wide range of samples that can be valid for conducting a kinship study. Within this variability, some samples may yield better results than others. We recommend that you get in touch with us so that we can advise you and increase the likelihood of successful results.