ANNUAL REPORT - Department of Biotechnology

programme is under implementation since 1990-91
with the objective to identify, map and characterize
genes related to genetic disorders prevalent in India
for diagnosis; prevention and management of
genetic disorders and to develop new methods for
the analysis and interpretations of genomic DNA
sequences. Further, based on a strategic meeting
held in August, 2000, several new major initiatives
were taken based on the announcement of Human
Genome Sequences under International Human
Genome project and the information available in the
public domain to identify genotypes associations
with varied clinical symptoms of different diseases
and disorders. These were aimed at better molecular
diagnostics and preventive strategies including
vaccines, new drug targets, which would lead to
development of new drugs with customized use in
patients/subjects.
Significant achievements during the year are as
follows:
Genetic Diagnosis cum Counseling Units
The genetic unit established at CMC, Vellore on
Molecular Genetics of Thalassemia, Hereditary,
Bleeding Disorders and Leukemia”, collected
samples from 225 patients and screened β globin
gene mutations and these were characterized by
DNA sequencing. Further 4 rare mutations that have
not been reported earlier in the Indian population
were identified. Common α globin gene deletions
were screened by multiplex PCR in the
heterozygous. Alpha globin triplications and
quadruplications were screened by a multiplex PCR
approach, In the area of leukemia diagnosis, the
group has standardized the quantitative real time
PCR for several transcripts. Excellent infrastructure
has been established to undertake advanced
molecular genetic research in blood disorders and
providing services for bone marrow transplantation
for thalassemia patients.
Under the project “Characterisation of mutations
underlying Hemophilia A and B” at AIIMS, New Delhi,
143 samples of Hemophilia A&B have been collected
and DNA extracted from 78 samples. The
Conformation Sensitive Gel Electrophoresis (CSGE)
has been standardized which can accommodate
small and thick gels. Linkage markers are being
used for carrier detection in females with a positive
family history of Hemophilia A&B and the females
with affected fetus are being advised to abort the
fetus.
In the multi-centric project on Methotrexate in
Rheumatoid Arthritis: Pharmacogenenetics and
Clinico-Immunoogical correlates implemented at
AIIMS, R&R Hospital and UDSC, New Delhi, 292
cases of rheumatoid arthritis [AIIMS=210, R&R
Hospital=82] were recruited and patients were
classified into methotrexate responder and nonresponder
phenotypes as per the criteria described
in the project. The DNA was isolated from a total of
292 samples and 267 samples have been analysed.
Two approaches were used for the genetic analysis
i.e. (1) re-sequencing of selected genes to identify
novel SNPs and validate published SNPs in a small
number of control samples, (2) genotyping of
published SNPs and novel ones identified from (1)
above in responders and non responders to MTX.
Further one novel SNP in exon 5 of RFC gene has
observed and its analysis is in progress.
In the project implemented at JIPMER, Pondicherry
on “Genetic susceptibility to essential hypertension
in a South Indian Population”, standardization of
genotyping procedures for ATI polymorphism, eNOS
polymorphism and ACE polymorphism were done
using PCR-RFLP and multiplex PCR methods. Allele
specific PCR method was done using primers. DNA
analysis of eNOS (Glu298Asp) and ATI (A1166C)
polymorphism were carried out by PCR-RFLP
method using Mbo1 and Dde1 restriction enzyme
respectively. It was observed that individuals in the
Tamilian population, with I/I genotype had an
increased risk for hypertension when compared to
D/D genotype, but the difference was not statistically
significant. The A/A genotype occurred more
frequently in cases when compared to control.
Others
119 Research and Development