We are all beautiful creations! But what makes you unique is your genes, it is the beautiful concoction of mutations entwined in your DNA. However, it is important to understand that mutations are two folded, that is, they can be beneficial and/or harmful. Hence, a proper analysis of your genes becomes of paramount importance. Genetic testing looks for alterations in your DNA, evaluates them, and weaves a complete understanding of your health and well-being.
Variant Genetics provides genetic testing for pregnant women, newborns, children and, people of all ages. Diagnosis of genetic diseases is done in 3 steps:
- Preliminary examination (by a clinician),
- Genetic counselling and
- A Genetic test.
At the time of your appointment, our team member (a genetic counsellor or clinical geneticist) will review your medical and family history and guide you for tests. We offer you a wide spectrum of tests tailored for your diverse needs.
- Diagnostic Testing: is used to identify or rule out a specific genetic or chromosomal condition in person if symptoms of a disease that may be caused by genetic alterations (Genetic Variants) are present
- Newborn Screening: is used for checking certain genetic disorders that can be diagnosed and treated for early disease management
- Prenatal Diagnosis: is used to diagnose a genetic disease in developing fetus (from blood, amniocentesis, chorionic villus sample)
- Preimplantation Testing: is used only in IVF (in-vitro fertilization) to check genetic disease in the embryo before implantation
- Carrier Testing: to identify the carrier status of a person for certain genetic conditions.
- Pre-symptomatic Testing: checks certain genetic alterations that are associated with disease, in case of a person with a family history of a genetic disease
- Predictive Testing: tells a healthy person with or without a family history, the probability of development of certain disease
Genetic Testing of Inherited Diseases
While mutations can make or break you, make a clean break with ClinoVar! ClinoVar from Variant Genetics is a genetic test to stop, that assures accurate identification of the the root cause of a genetic disease that directly influences patient upshots and disease management. We aim at applying scientific-driven knowledge for finding genetic variations associated with health and to appraise one towards making conscious efforts for a healthy and hearty life.
Genetic disorders can be chromosomal disorders or single-gene disorders. In humans, there are 23 pairs of chromosomes, which are made up of DNA that condenses and finally forms several genes. When a disorder results from alterations in the entire chromosome, it results in chromosomal abnormalities. Examples for this include Down syndrome where three copies[trisomy] of the 21st chromosome are seen[ duplication of a chromosome], or Cri-du-chat syndrome where deletion is seen in the 5th chromosome. On the other hand, when a mutation occurs at a particular location in a single gene, it results in single-gene disorders. Cystic fibrosis and sickle cell anemia are some of the single-gene disorders.
Out of the 23 pairs of chromosomes, 22 pairs are known as autosomal chromosomes and the last pair is known as sex-linked chromosomes. The 23rd pair can be XX, as in females, or XY, as in males. Apart from this, mutations can also be classified as dominant mutations where only one copy of the mutation is sufficient to cause a disorder or recessive mutations where two copies of the mutation are required for the disease to be expressed. Based on this classification, there are four main ways in which one inherits genetic disorders:
Autosomal dominant: A genetic disorder that results from a dominant mutation seen on autosomal chromosomes, where either of the parents expresses the disease. The mutation is passed on to the next generation invariably and 50-100% of the progeny are affected.
EXAMPLES: Huntington’s disease
Autosomal recessive: A genetic disorder that results from a recessive mutation seen on autosomal chromosomes, where in order to pass it to the next generation both the parents have to be carriers of the mutation. 25-50% of the progeny are affected.
EXAMPLES: Cystic fibrosis, Phenylketonuria (PKU)
X linked dominant: A genetic disorder that results from a dominant mutation on the X chromosome. 50-100% of the progeny are affected.
EXAMPLES: Vitamin D-resistant rickets
X linked recessive: A genetic disorder that results from a recessive mutation on the X chromosome. Males are more frequently affected. 25-50% of the progeny are affected.
EXAMPLES: Hemophilia, DMD
Tests @ ClinoVar
- Alpha Thalassemia
- Beta Thalassemia
- Sickle Cell Anemia
- Hemoglobin E disease
- Hemophilia A
- Duchenne Muscular Dystrophy
- Becker Muscular Dystrophy
- Spinal Muscular Atrophy
- Myotonic Dystrophy
- Spino Bulbar Muscular Atrophy (SBMA)
- Spinocerebellar Ataxia
- Huntington Disease
- Fragile X syndrome
- Fredrich Ataxia
- Dentatorubral Pallido Luysian Atrophy (DRPLA)
- Leigh Syndrome
- Non-Syndromic Hearing Loss (NSHL)
- Cystic Fibrosis
- Chronic Pancreatitis
- Glucose 6 Phosphate Dehydrogenase Deficiency
- Polycythaemia Vera
- Gilbert Syndrome
- SRY gene deletion
- Factor V
- Factor II
- Hereditary Haemochromatosis
What is cytogenetic testing?
Cytogenetic testing is the chromosomal analysis of blood to look for chromosomal level alterations in the genome. This test can examine chromosomes to determine abnormalities such as aneuploidy and structural abnormalities.
Aneuploidy involves having one or more extra chromosomes or having missing chromosomes from 23 pairs of chromosomes. Some common aneuploidies that can be detected by cytogenetic testing are Down Syndrome (trisomy 21), Edward’s syndrome (trisomy 18), Turner syndrome (monosomy X), DiGeorge Syndrome (monosomy 22) etc. Various types of structural abnormalizes can also be detected such as Duplication, Deletion, Translocation, and Inversions.
Tests we offer
- Rapid Aneuploidy detection (Chromosome 13, 18 and 21)
- MLPA panel for common microdeletion syndrome
- Array Comparative Genomic Hybridization Assay (aCGh)
- Fluorescent in Situ Hybridization (FISH)
Karyotyping is an analysis of chromosomes using staining of cells at metaphase and examination under light microscopy. Standardized staining procedure develops characteristic banding pattern, that helps in the identification of chromosomes. Karyogram is 23 pairs of chromosomes typically organized for analysis. Karyotype identify chromosomal abnormalities, change in chromosome number (aneuploidy) and change in the structure of chromosomes (translocations, inversions, deletions, duplications).
Multiplex Ligation-dependent Probe Amplification (MLPA) is a technique for the detection of copy number variation (deletion or duplication) of specific genes. Several genetic disorders such as Duchenne Muscular Dystrophy (DMD), Spinal Muscular Atrophy (SMA) is commonly caused by gene deletion or duplications.
Array CGH Testing
Array CGH testing is considered as a frontline test for patients with the presentation of developmental delay, autism spectrum disorders, learning difficulties, dysmorphisms and with or without congenital abnormalities.
Array CGH detects microdeletions and duplications (Copy number variations CNVs) that are not detected by karyotyping.
When to take this test?
Patient with following conditions (one or more):
- Developmental delay
- Mental retardation
- Autism / Autism spectrum disorders
- Congenital malformations
- Dysmorphic Features