New generation sequencing: a sequencing service step by step

Since its advent in the 1970s, DNA and RNA sequencing has revolutionised the scientific landscape. A multitude of research projects in fields as diverse as virology or anthropology, including oncology, the study of hereditary diseases or zoology, benefit enormously from access to DNA sequencing techniques. However, most centres do not have their own sequencing service.

The equipment and technical knowledge necessary to perform and process massive DNA sequencing is not available to all research groups. Whether through high-throughput sequencing, using in-vitro, ligation or parallel amplification, the fact is that achieving reliable results in a project like this is critical, which is why most research groups turn to the outside for a sequencing service.

However, the sequencing process neither begins nor ends in the laboratory, and previous steps, such as sample collection, or subsequent steps, such as data analysis, are crucial so that DNA sequencing does not end up inconclusive.

1. AN OPTIMAL SAMPLE COLLECTION
An essential step in any genetic study is the collection of samples. Especially in the case of human genetic studies, obtain an acceptable sample size and diversity, as well as the consent and voluntary collaboration of those involved.

In the past, blood extraction was used as a method for DNA analysis; However, the need to refrigerate samples for preservation and patients’ rejection of an invasive sampling method has led human genetics researchers to look for an alternative.

Today, most researchers use saliva samples as an alternative to blood collection, since it does not present any of the problems of blood collection. Among solutions for non-invasive sampling, the market leader is DNA Genotek, which allows the extraction of human and microbial DNA and RNA from saliva, faeces, or mucus samples.

2. SAMPLE DELIVERY
Thanks to DNA Genotek sample preservation technology, sample shipping is cheap, simple, and can be done at room temperature once all samples have been collected.

Since the collection method allows them to be stored without refrigeration for up to a year without losing the quality of the DNA, in less than two days your samples will be in the laboratory ready to be sequenced.

3. SEQUENCING
The sequencing service begins with the extraction and purification of DNA from the sample. Given the sensitivity of the machines and methods used in the process, it is essential that any possible impurity of the sample be eliminated from it.

That is why, after DNA extraction, the sample goes through a strict quality control process, in which not only is the DNA purified, but it is checked whether there is enough genetic material in the sample to allow sequencing.

Once the sample has been treated appropriately and its quality has been demonstrated, the construction of the libraries begins. After reducing the DNA strand of the sample to smaller fragments using ultrasound or enzymes, each fragment is enriched with adapters that allow subsequent identification of said fragment.

The next steps depend on the type of sequencing to be carried out; the technology and sequencer to be used, and the purpose of the research.

Massive NGS sequencing using Illumina technology allows the sample to be sequenced base by base, very precisely, eliminating practically all sequence errors inherent to the context. This technology allows you to:

- Short genome sequencing
- 16S metagenomics
- AR sequencing
- Selective re-sequenciation
- Preimplantation genetic analysis (PGA)
- Analyse direct genetic expression profiles

Massive NGS sequencing using Ion Torrent technology allows high-throughput sequencing to be performed in less time and at a low operating cost. Thus, it allows sequencing in a highly efficient way:
- Microbial genomes
- Exomes
- Transcriptomes

Capillary sequencing is based on the Sanger sequencing method, being an automated Sanger sequencing methodology. This method performs an electrophoresis process after DNA amplification incorporating labelled dideoxynucleotides. This methodology allows:
- Polymorphism genotyping (SNPs)
- Genetic Fingerprinting
- Fragment analysis STR

4.DATA ANALYSIS AND BIOINFORMATIC SERVICE
Although in all projects we deliver the raw data just as it comes out of the sequencer, we also offer a bioinformatics analysis service that compares all the extracted sequences with the genome of the species.

This allows the researcher to save a considerable amount of work and raw data processing and focus on the part of their research that truly matters, always having access to the original data to be able to verify the process and use it in the future if necessary.

IN CONCLUSION

Through a comprehensive service that cares about your research from the moment the sample is taken until the data analysis, at Abyntek Biopharma we guarantee our clients the most complete external sequencing service on the market.

If your team is capable of taking charge of any part of the process, either because the samples have already been taken; or why your bioinformatics team can take charge of the data, each of the steps of this service can be contracted separately, which allows us to help many more investigations to come to fruition.

At Abyntek Biopharma we have been dedicated to providing the best possible service to researchers for more than 15 years. That is why we not only put all our know-how and experience in helping thousands of scientists to find the perfect reagent for their research, but we have gathered all the experience of our scientific department in creating support documents like these that guide and help researchers in their daily lives.