a. Genetic Counselling
Genetic counselling is valuable to people who are considering taking up a genetic test. With specialized training in medical genetics and counselling, a genetic counsellor* is well-positioned to guide counselees and their family members through the process of genetic testing that could be described in four stages:
1. Comprehension: The genetic counsellor would assess the counselee’s medical history and family history for the genetic conditions of interest. The basis/rationale, benefits and risks of a genetic test would be communicated to the counselee in a cordial dialogue. At the end of this session, the counselee will be adequately informed and confident to decide whether to take up a genetic test or not.
2 Decision: The genetic counsellor provides a non-directive assistance in the counselee’s decision-making process by giving vital and unbiased information. Once the counselee has decided to take up a genetic test, an informed consent would be obtained and the counselee could be guided for collection of sample.
3. Interpretation: Once the genetic test report is out, the outcome/result and any recommendations would be explained to the subject/counselee.
4. Solution: Health management options (if any) would be explained to the subject/counselee, so that informed choices could be made for the best of the subject/counselee and family members.
*A medical doctor with good experience in genetic testing may take up the role of a genetic counsellor.
b. Sample Collection
Two tubes of venous blood (5 mL each) will be collected by a medical professional in EDTA collection tubes*. The blood samples will be barcoded to ensure that the samples are “locked” to the subject and the subject’s identity and privacy are completely protected.
The samples will be transported in a secured manner to our accredited laboratories for DNA extraction and DNA sequencing.
*Lavender-Top Tube (EDTA): This tube contains EDTA as an anticoagulant and is used for most hematological procedures. Note: After the tube has been filled with blood, immediately invert the tube several times to prevent coagulation.
c. DNA Sequencing
DNA sequencing is done using the BGISEQ-500 high-throughput Next-Generation Sequencing (NGS) platform.
BGISEQ-500 is an industry leading high-throughput sequencing solution, powered by combinatorial Probe-Anchor Synthesis (cPAS) and improved DNA Nanoballs (DNB) technology.
The cPAS chemistry works by incorporating a fluorescent probe to a DNA anchor on the DNB, followed by high-resolution digital imaging. This combination of linear amplification and DNB technology reduces the error rate and enhances sequencing accuracy.
d. Analysis and Result Interpretation
Our team of bioinformaticians is supported by cutting-edge cloud solutions that integrate high-performance computing, secure networking and large-capacity storage to streamline big data analytics.
The completed clinical grade DNA sequence is analysed and studied comprehensively against large established databases through the use of numerous established algorithms and software. The databases examined encompass population, disease and sequence databases (e.g. Exome Aggregation Consortium, Human Gene Mutation Database, NCBI Genome, other restricted databases, our proprietary databases, etc.).
A final interpretation and a concise report is made by our American College of Medical Genetics and Genomics (ACMG) certified geneticists based on the standard ACMG guidelines.