A now-deceased Dutch doctor in charge of a sperm bank is likely to have fathered at least 19 children through IVF treatment, a comparison of their DNA revealed on Tuesday.
The Dutch institute known as FIOM which is charged with investigating the case said it compared DNA made available by a legitimate child of doctor Jan Karbaat who died last month, with 19 people born from IVF treatment.
"The DNA from the legitimate child matches that of 19 half-brothers and half-sisters," the FIOM said in a statement.
Tests however should continue in order to ensure a 100 percent match between the legitimate child and Karbaat's DNA, the FIOM's director Ellen Giepmans told AFP.
Karbaat's case hit the headlines earlier this month after a group of Dutch 23 people born from IVF treatment petitioned a court to seek DNA tests on the former head of the sperm bank to see if he was their father.
The children and their parents claim that Karbaat, who died aged 89, may have used his own sperm instead of that of the chosen donor at the fertility clinic he ran close to the port city of Rotterdam.
Karbaat reportedly admitted to having fathered about 60 children in his time at the clinic, which closed in 2009 amid reports of irregularities.
The lawyer for the 23 highlighted some inconsistencies such as one of his clients having brown eyes when the sperm donor was supposedly blue-eyed, or that another male client physically resembled the doctor.
The Karbaat family's lawyer in turn firmly denied the accusations and urged the court to respect the family's right to privacy.
Court officials on May 2 at the request of the families seized some personal objects such as a toothbrush from Karbaat's home but DNA tests have not been done.
The court is expected to hand down a ruling on the tests on June 2.