Genetic Disorders, Chromosome Analysis, Karyotyping, cytogenetic analysis, Ambiguous genitalia, Dysmorphic features, G-banding, C-banding, DA-DAPI, Chromosomal breakage studies, Fanconi anemia, Sister chromatid exchange, Fragile X, Ataxia telangiectasia, Low grade mosaicism, Down syndrome, Turner Syndrome, Klinefelter syndrome, Microdeletion detection, FISH for microdeletion, Prader Willi syndrome, Angelman Syndrome, Williams Syndrome, DiGeorge syndrome, Trisomy, Monosomy, cultured blood, buccal cells, urine cells, chorionic villi, placenta, ultured fibroblasts, products of conception (POC), Bleomycin, mosaicism, lymphocytes, chromosome 15, chromosome 22, cleft palate, Autism, uniparental disomy

Karyotyping from blood (routine)
Indications for cytogenetic analysis:

Children with-

Dysmorphic features
Mental subnormality
Congenital anomalies
Ambiguous genitalia
Hypogonadism / undescended testes / hypospadias
Delayed menarche and short stature

Sample: 2-3 ml blood in sodium heparin vaccutainer (green top tube) transported at room temperature

Other banding techniques
In addition to G-banding, specific staining techniques such as C-banding, DA-DAPI staining,Quinacrine fluorescence etc. are also offered on request.

Chromosomal breakage studies Radial in Fanconi Anemia
The diagnosis of chromosome breakage disorders such as Fragile-X, Fanconi anemia, Ataxia Telangiectasia, Sister Chromatid exchnage and Blooms syndrome involves addition of chromosome breakage inducing agents specific for each disorder, to the blood culture. The test is run simultaneously with blood of a matched control. Multiple cultures of the patient and control samples are set up. A positive sample will show a higher frequency of breaks, fragile sites, radial figures or sister chromatid exchanges, compared to the control.

Sample: Blood (3 ml in sodium heparin) from patient and age/sex matched control transported at room temperature

Detection of low grade mosaicism
Patients with low-grade mosaicism can be detected with FISH techniques. This technique is very useful to rule out common numerical chromosome abnormalities like Down syndrome, Turner syndrome, Klinefelter Syndrome, monosomy, trisomy etc. Different varieties of tissues can be used such as lymphocytes from direct or cultured blood, buccal cells, urine cells, chorionic villi, placenta, cultured fibroblasts, products of conception (POC) etc. The report is available within 2-3 days. Presently we have probes for chromosomes 8, 9, 13, 15,16, 17, 18, 21, 22, X and Y in different combinations.

Microdeletion detection by FISH
Prader Willi syndrome and Angelman syndrome are two separate clinical conditions caused by a microdeletion on chromosome 15. Microdeletions are often missed by karyotyping, but are easily detected by FISH on cultured lymphocytes. Occasionally, these syndromes may be caused by a mutation or uniparental disomy instead of a deletion. FISH using specific probes can only pick up cases caused by deletions.

Microdeletion Test: Deletion absent

Microdeletion Test: Deletion present

Certain cases of Autism are caused by duplication of the same region on chromosome 15, instead of a deletion.

DiGeorge syndrome is caused by a microdeletion in chromosome 22 and is associated mainly with cardiac defects in children, together with cleft palate and learning problems. Seizures, hypocalcemia and hypoplasia of parathyroid glands is also known to occur.

Williams syndrome is caused by a microdeletion on chromosome 7. The main clinical features are supravalvular aortic stenosis, elfin face and mental retardation.

We offer the FISH test for these microdeletion syndromes.

Sample: 2-3 ml blood in sodium heparin vaccutainer (green top tube) transported at room temperature.