Human genetic analysis is carried out applied to Genetic Diagnosis of hereditary conditions and Forensic Genetics. The most advanced techniques are used to identify alterations in the DNA sequence related with the appearance of hereditary illnesses, both the more common ones and, above all, those known as Rare Diseases. We also carry out pre-natal genetic analyses aimed at discovering, during pregnancy, any congenital defect or development anomaly which might be present at birth.  

The must usual applications are: 

  • Reproduction: Non-invasive prenatal diagnosis 
  • Tests of paternity, maternity, relationship, genetic fingerprint   
  • Cytogenetics and molecular genetics  

Molecular biology

Molecular biology is a discipline which studies biological processes at the molecular level, in the interactions between the different cell systems, including nucleic acids (DNA and RNA) and proteins.

This is closely linked to other disciplines like Genetics (genetic studies); Biochemistry (studies of the enzymes and proteins); Microbiology (identification of microorganisms and relevant features); Haematology; Immunology, etc, etc.

The techniques of molecular biology applied to the laboratory have increased our ability to understand, diagnose and treat a great range of illnesses.

Most-used methods

The majority of the techniques of molecular biology used in clinical laboratories have their basis in the Polymerase Chain Reaction (PCR). This reaction allows for the amplification of known DNA fragments, so that they can subsequently be detected by means of different variants. These techniques allow us to have great sensitivity and analytical specificity.

The most usual are:

Detection by means of melting temperature):

The fragments of amplified DNA are subjected to growing temperatures so that the double strand dissociates itself at a specific temperature from each target. Different amplified fragments dissociate themselves at different, known temperatures and that allows them to be identified with great discriminatory capacity. Detection generally arises through the measurement of a fluorescent signal produced when the DNA chain dissociates itself.

Detection and quantification by means of PCR in real time:

Real time PCR consists of a classic amplification with the exception that the quantity of fluorescence produced after each amplification cycle is measured. As there is an exponential increase in DNA from a certain phase of the reaction, that increase in signal can be quantified, in such a way that we would know the quantity of target DNA that was present in the original sample.

A variant of this technique is to carry out the quantification of RNA (HIV virus, VHC viruses which are RNA viruses). In order to carry out the quantification first a step from RNA to DNA is carried out via an enzyme called inverse transcriptase. Subsequently, the rest of the process is the same.

At Eurofins LGS Megalab, we carry out different techniques based on these essentials. After the extraction of genetic material, the mixture of different reactives is carried out and they are put into the leading-edge equipment, which is ready to carry out the techniques we are speaking of. Currently, the genotyping of the Human Papilloma Virus is carried out together with the detection of sexually transmitted pathogens by real time PCR and melting; and the viral loads of the Hepatitis C Vir, Human Immunodeficiency Virus, detection of Mycobacterium tuberculosis complex, and detection and genotyping of Factors II and V of coagulation by means of real-time PCR in a piece of automatic equipment.