Genetic Laboratory Testing
What is Genetic Laboratory Testing?
Genetic Laboratory testing is a vital medical examination that identifies changes in genes, chromosomes, or proteins, contributing to the confirmation or exclusion of suspected genetic conditions and helping assess the risk of developing or passing on a genetic disorder. With over 77,000 genetic Laboratory tests currently available and ongoing developments, the testing process encompasses the identification of alterations in genes, chromosomes, and proteins.
Genes: Gene tests scrutinize DNA sequences to pinpoint variations (mutations) that can cause or increase the risk of a genetic disorder. These tests vary in scope, analyzing individual DNA building blocks (nucleotides), one or more genes, or an entire genome.
Chromosomes: Chromosomal genetic Laboratory tests evaluate entire chromosomes or extensive DNA segments to detect significant genetic changes, such as an extra chromosome, indicative of a genetic condition.
Proteins: Biochemical genetic tests assess the quantity or activity of proteins or enzymes, signaling changes in DNA and potential genetic disorders.
Participation in genetic testing is voluntary, and the decision is personal and intricate, taking into account the benefits, limitations, and risks involved. Geneticists and genetic counselors are essential in providing information on the pros and cons of testing, and addressing the social and emotional aspects associated with it. Genetic laboratory testing and genetic testing laboratories play pivotal roles in conducting these tests, contributing to advancements in understanding and managing genetic conditions.
How is Genetic Testing Done?
Once someone decides to undergo genetic testing, their healthcare provider can facilitate the process, often as part of a genetic consultation. Samples for testing are typically taken from blood, hair, skin, amniotic fluid, or other tissues. For instance, a buccal smear involves collecting cheek cells with a small brush or cotton swab. These samples are sent to a lab where technicians analyze chromosomes, DNA, or proteins, depending on the suspected disorder. Test results are then reported in writing to the person’s doctor, genetic counselor, or directly to the patient upon request.
Newborn screening, done by pricking the baby’s heel for a small blood sample, provides results mainly if positive. Positive results prompt further testing to confirm any potential genetic disorders.
Before undergoing genetic Laboratory testing, it’s crucial to comprehend the procedure, benefits, limitations, and potential consequences of the results. This education and permission process is termed informed consent.
Those interested in direct-to-consumer genetic testing services can obtain a test directly from the testing company without involving a healthcare provider. Positive results or a higher risk indication may prompt individuals to seek guidance from a genetic counselor or healthcare provider.
Who should Opt For Genetic Laboratory Testing?
Genetic Laboratory testing may be considered by individuals in various situations:
1. Family History of Genetic Disorders: If there is a known family history of a genetic disorder, individuals may opt for genetic testing to understand their risk or the likelihood of passing on the condition to their children.
2. Personal History of Genetic Conditions: Individuals who have personal experiences with genetic conditions or symptoms may undergo testing to confirm a diagnosis, guide treatment, or assess the risk of recurrence in the future pregnancies.
3. Pregnant Individuals: Pregnant women may opt for genetic testing to screen for chromosomal abnormalities or genetic disorders in the developing fetus. This can help in making informed decisions about the pregnancy.
4. Couples Planning for Pregnancy: Couples planning to have children may choose genetic testing to assess the risk of passing on certain genetic disorders to their offspring. This is particularly relevant for carriers of recessive genetic conditions.
5. Individuals with Unexplained Health Issues: Those with unexplained health problems or a family history of conditions with a genetic component may undergo testing to identify potential genetic factors contributing to their health issues.
6. Cancer Risk Assessment: Individuals with a family history of certain cancers may consider genetic testing to assess their predisposition to specific types of cancer. This information can guide personalized cancer screening and prevention strategies.
7. Individuals of Certain Ethnic Backgrounds: Some genetic conditions are more prevalent in specific ethnic groups. Members of these groups may consider testing to assess their risk and take preventive measures.
8. Preventive Health Planning: Individuals interested in proactive health management may opt for genetic testing to gain insights into their predisposition to certain conditions. This information can guide lifestyle choices and preventive measures.
What Diseases Can Be Detected Through Genetic Testing?
Genetic Laboratory testing is a powerful tool that can identify a range of diseases and conditions with a genetic basis. It covers various health areas, such as hereditary cancer syndromes (e.g., BRCA mutations), cystic fibrosis, hemochromatosis, Huntington’s disease, thalassemia, muscular dystrophy, neurological disorders (e.g., Alzheimer’s and Parkinson’s), inherited cardiac conditions, Lynch syndrome (associated with increased cancer risk), familial hypercholesterolemia, and various Mendelian disorders (e.g., sickle cell anemia). These tests help individuals understand their genetic predispositions, allowing for proactive health management and informed decision-making. The field of genetic testing continues to evolve, providing new insights into both rare and common genetic conditions. Genetic counseling is often recommended to assist individuals in interpreting and applying the information gained from genetic testing to their healthcare decisions.
What are the different types of genetic tests?
There are different types of genetic tests to check for changes in our genes, chromosomes, or proteins. When doctors choose a test, they consider what health conditions are suspected and the typical genetic variations related to those conditions. If it needs to be clarified what’s going on, a test that looks at many genes or chromosomes might be used. But if a specific condition is suspected, a more focused test may be done.
Here are some types of genetic tests:
1. Molecular Tests:
- ⦿ Targeted Single Variant: Looks for a specific change in one gene, often used in families with known genetic issues.
- ⦿ Single Gene: Checks for any genetic changes in one gene, confirming or ruling out a specific diagnosis.
- ⦿ Gene Panel: Looks for changes in multiple genes, helpful when someone has symptoms that could be related to various conditions.
- ⦿ Whole Exome Sequencing/Whole Genome Sequencing: Examines a lot of a person’s DNA, useful when a specific diagnosis is unclear.
2. Chromosomal Tests: Examines whole chromosomes or long DNA sections for big changes linked to certain genetic conditions.
3. Gene Expression Tests: Checks which genes are active or inactive in cells, offering insights into disorders like cancer.
4. Biochemical Tests: Assesses protein or enzyme levels, showing if there are changes in DNA that might cause a genetic disorder.
Starting years:
The department of genetics at Krishna IVF Clinic was started in the year 2005. Krishna IVF Clinic is the first infertility centre with integrated genetics department in the early 2005 in the states of Andhra Pradesh and Telangana. The genetics department was started with traditional cytogenetics, study of genetic disorders at chromosomal level known as karyotyping. In the early days karyotyping was done in the blood samples later extended to foetal samples amniotic fluid and CVS. After few years with the vision and persuasive skill of the team led to the birth of molecular genetics.
Team:
In the initial days the department was started with a team consisting of three persons Dr. G. A. Rama Raju, Dr. K. Madan and Dr. T. Sivanarayana.
Dr Rama Raju is the clinical expert in the field of reproductive medicine, Dr Madan is a pathologist and Sivanarayana is post graduate in human genetics. They made major developments in prenatal diagnosis, genetic counselling and management of patients with previous history of genetic disorders. Later it was extended with other geneticists Dr. Ch. Ravi Krishna, KPG Shankar and Dr. Aruna.
PGT consortium:
Krishna IVF Clinic is first clinic which participated in the annual data collection and is registered as a full member of the ESHRE (European Society of Human Reproduction and Embryology) PGD Consortium for the year 2008, and PGD data published on ESHRE PGT consortium data collection XVI-XVIII: Cycles from 2013 to 2015, Human Reproduction open, PP. 1-11, 2020. doi: 10.1093/hropen/hoaa043.
Research Centre:
Krishna IVF Clinic is recognized as an extramural research centre for pursuing Ph.D program from Andhra University in year 2008 and GITAM University in the year 2016 on the recommendations of the board of research studies from the respective university members. This program helps postgraduate students to pursue their Ph.D program at Krishna IVF Clinic and doctorate will be awarded by the respective universities. Till date three members have completed their Ph.D program from department of genetics and two members are pursuing their Ph.D from clinical department.
- First Ph.D : T. Sivanarayana pursued his Ph.D on DNA Fragmentation of human spermatozoa: Effects on sperm morphokinematic and embryological parameters in assisted reproductive program.
- Second Ph.D: Ch. Ravi Krishna pursued his Ph.D titled, A study on influence of AFC, AMH and FSHR gene polymorphisms on ovarian response and clinical pregnancy outcome in patients undergoing controlled ovarian stimulation using r-FSH in combination with LH
- Third Ph.D: Dr. G. A. Rama Raju pursued his Ph.D titled, A study on the development of deep learning techniques and the use of hormonal and genetic approaches for achieving better success rates in long GnRH agonist treated IVF cycles.
Research Publications:
Krishna IVF is involved in research activities along with regular clinical practice. As a part of research activity, the team has published few papers in the field of male and female reproductive genetics.
Male infertility: Krishna IVF has studied extensively on the role of Sperm morphology, Sperm DNA fragmentation and male diabetic conditions and their outcome of the ART cycles.
Female infertility: One of the outstanding works performed by Krishna IVF Clinic is pharmacogenomic approach of LH supplementation in COS protocols based on polymorphic variants of LH receptor. The foundation for the project was laid in the early 2010 with the visionary purchase of 3500 genetic analyser from Thermofisher scientific which is based on sanger sequencing principle. With the help of sanger sequencing, we performed retrospective and prospective study on the role of genetic polymorphisms in controlled ovarian stimulation protocols. To our knowledge this is the first study at the time of publication to define the pharmacogenetic approach of LHCGR polymorphisms on LH supplementation.
Services:
The genetics laboratory contributes to the advancement of genetic testing with a goal of improving patient care. Krishna IVF provides genetic diagnostic services both in the field of cytogenetics and molecular genetics. In cytogenetics we offer karyotyping on all type of samples including peripheral blood, amniotic fluid, CVS. In molecular genetics we provide testing of viral and bacterial infections that are sexually transmitted and related to infertility using real-time PCR, we provide sequencing for single gene mutations. We provide full gene sequencing for HBB, FSHR, LHCGR, CFTR, few deafness related genes (GJB2, GJB3, GJB6) and AURKC. Hot spot variants for MTHFR and Annexin A5.