Fraudulent Fertilisation

“Doctor Zimbrein, thanks very much for coming,” said Roberto. “It’s a great honour to receive you in Mar del Plata. As I told you, tomorrow is the deadline for contesting the lawsuit. Everything’s already prepared, all that’s left is to insert your report.”

They were in Burán’s office. Rocío had asked Doctor Saúl Zimbrein to explain the filiation report to them personally. The distinguished scientist, as humble as he was wise, played down the importance of his presence...

“Relax, Doctor Burán, I came because I’m on holiday in Mar del Plata. It was no effort to come and visit, why should you travel to Buenos Aires if I was going to come here? Believe me, to have everything ready in such a short time was almost a miracle. The reports from the United States were sent to me by fax, the originals will soon get here. To cut a long story short, I’ve got important news for you...”

Anxiously, Roberto asked, “Have you got the results of the test, is it finished?”

“Yes, Doctor, I can tell you with absolute certainty that you are the father of little Agustín. You can claim your rights as a father without hesitation, they correspond to you.”

Roberto didn’t know what to say. Unconsciously, he took Rocío’s hand. He let go of it quickly so as not to make evident the intimacy he enjoyed with her. Coming out of his perturbation, he said:

“Doctor Zimbrein, you will understand that your opinion is important to me, have you taken every precaution? Did you consult institutes in the United States of America? You told me you intended doing so...”

“I kept my promise, Doctor Burán, I already told you I received them by fax... Don’t worry, there’s no chance of a mistake. I’ll explain in greater detail, so that you can understand it better. The first question we ought to ask would be the following: can the filiation of a person be proved with certainty, solely based on human biological material?”

“We understand the answer is yes,” said Rocío.

“And you’re not wrong, doctor, that’s really the case... There’s an examination called ‘DNA classification’, or ‘DNA fingerprints’ or ‘securing the DNA profile’. It’s decisive in the determination of a filial link, regardless of the existence of other means of testing.”

“I read something,” said Roberto, “I think they condemned a rapist in London thanks to the genetic analysis of his semen, am I wrong?”

“That’s right,” answered the scientist, “nowadays, rapists don’t act with the same impunity as before. They inevitably leave their mark, an equivalent of a fingerprint. The study of DNA allows us to improve on all previous techniques, even the most recent ones, such as, for examples, immunological examinations.”

Roberto went on asking questions:

“What is the method you used based on, Doctor Zimbrein?”

“Very simply, on the genetic diversity that exists in all species, even in plants. These differences are those which determine the existence of different blood groups... They make us possess some specific enzymes or proteins that others don’t have.”

“I’ve read something about the histocompatibilty examination known as HLA, I’ve been told it’s almost infallible.” Roberto commented.

“We’ve done it, Doctor Burán, you’re referring to the Human Lymphocity Antigen, it’s based on a study of antigenic proteins. I admit it’s quite precise, but I must point out that we’ve used another, newer method, which is even more effective. The one you mention is based on approximation, it shows the differences between individuals to achieve an indirect identification, computing the uncommon similarities.”

“I didn’t know such an advanced system existed,” said Roberto.

“Believe me, there’s another which is much better... When classifying the sample extracted from Ms Juana Artigas, her son and yourself, we have directed ourselves straight to the deoxyribonucleic acid, that is, the DNA. The genetic information is encoded there. This is what determines that we are men, and not rats. It’s even the reason I’m short and fat and my cousins are tall and slim. DNA is in all of our cells, in their nuclei, with the exception of red corpuscles.”

Rocío was puzzled:

“I don’t understand, Doctor Zimbrein, didn’t you extract blood to carry out the test?”

“Yes, that’s true, but it contains other elements; the DNA is extracted from the leucocytes, also known as white corpuscles. In fact, any sample can be used, such as, for example, semen, hair roots, or any other tissue, even bits of skin. They can be classified as ‘biological identity cards’; it’s absolutely trustworthy.

Burán was curious:

“Was it very expensive, Doctor? I understand it must be very complicated to carry out these studies...”

“Don’t you believe it, it’s probably cheaper than you imagine. I sent the material to two top-flight institutes in the USA. One of them, Tradcell, invoiced me for six hundred dollars to analyse the three extracts. Of course, I mean those obtained from yourself, your son and Juana Artigas. Another entity, Booklife, charged me less, only four hundred dollars. To put your mind at ease, I must tell you that both reports coincided. There’s no doubt about your paternity, consider it certain...”

Rocío showed interest in the subject:

“How is it done, doctor? Is it difficult to understand?”

“In detail, yes. But it’s possible to give a generic approximation of what it’s about. Look, a part of the DNA isn’t encoded; this was discovered by Doctor Alec Jeffreys very recently. Think about it, this find was patented in 1987. Well, this apparently useless segment of DNA is dispersed and contains elements that are highly variable from one individual to another, and which are transmitted according the laws of heredity. To sum up, using this procedure, it’s possible to analyse these sequences which don’t show so much variation between related people.”

“Is that all?” said Roberto.

“If I were to explain it in detail, you wouldn’t understand; make do with that brief image. The means and techniques used are very complicated. The diagram obtained is similar to those bar code labels they use in the goods in a supermarket; you have to know how to read them. The fact is that comparing those that correspond to different samples, you can see whether or not there is a filial link. If you were to analyse the genetic material of the same individual, the labels would be identical.”

“So it was shown that the semen deposited by Álvez was mine?” said Burán.

“No doubt about it, the DNA was recovered from the heads of the spermatazoons present in that material, the genetic fingerprint is yours.”

Roberto wanted more information:

“How can you be sure? Doesn’t the passage of time have any influence?”

“Doctor Burán, I can assure you that your DNA is stable. Just think about this: genetic ‘labels’ have been extracted from Egyptian mummies... A few centuries have gone by for them, haven’t they? Enormous progress is being made in these matters; lately, they’ve been applying an even more sophisticated version... It’s to do with the molecular analysis of a single point, applicable when the sample obtained is negligible, or is very degraded. They can do it using a blood stain the size of a pinhead as material, or the root of a hair.”

Doctor Rocío Bareilles interrupted them:

“Excuse me, Doctor Zimbrein, I’d like to ask you a question: what degree of certainty does your report offer?”

“I’ll answer you in figures. We’ve compared twenty genetic ‘bands’ in the case. It could be said that in our supposition, the possibility of casual coincidence existing is one in a million, do you think that’s enough?. I can tell you that with the HLA method, the maximum that can be obtained, in optimum conditions, is 98·85 percent certainty. In any case, I inform you that I myself used the histocompatibilty system. I did it with the collaboration of scientists at Durand Hospital, in the city of Buenos Aires, obtaining a similar result. The margin of error, according to that study, is five percent... As you can see, you can be certain.”

Burán was pleasantly surprised, the report would allow him to act more energetically, to assume to role of Agustín’s father definitively.

“Doctor Zimbrein, I congratulate you, I never thought you’d be so efficient. It’s a source of pride to have a investigator such as yourself in Argentina, you’ve more than earned your fees, I’m very satisfied. I’ll sign you a cheque right now, OK?”

“That was the agreement, regrettably we all have to live, perhaps free analyses would be ideal... Among the instruments I leave you, there are the conclusions of the United States institutes we consulted. I had them translated so that the judges can interpret them properly... I’m glad I’ve been useful, consider me at your disposition should any doubts arise. I wish you all the best of luck. I know you’ll be a good father, Doctor Burán: I’m happy to have benefited your baby. See you soon...”