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We are fascinated with the question of human origin.

Palaeontology and archaeology are the branches that traditionally deal with the reconstruction of human origin and history.

Molecular biology is contributing to this area through DNA analysis.

HUMAN GENOME DIVERSITY PROJECT

HUMAN GENOME DIVERSITY PROJECT SEEKS TO UNDERSTANDTHE GENETIC RELATIONSHIP BETWEEN DIFFERENT POPULATIONSBY USING STANDARD DNA MARKERS LIKE

mtDNA

“Y” CHROMOSOME

HGDP IN INDIA- CCMB IS ONE OF THE PIONEER INSTITUTE WHICH IS ANALYSING PRIMITIVE TRIBES AND CASTE AT MOLECULAR LEVEL. AROUND 6000 BLOOD SAMPLES OF DIFFERENTPOPULATIONS HAVE BEEN ANALYSED FOR THEIR GENETIC DIVERSITY

TWO HYPOTHESES REGARDING EVOLUTION OF MAN

OUT OF AFRICA THEORY

MULTI REGIONAL THEORY

MITOCHONDRIAL DNA IS COMMONLY USED IN THE CONSTRUCTION OF EVOLUTIONARY TREES.

EVOLUTION OF MAN

MITOCHONDRIAL DNA WAS FIRST RECORDED BY

ELECTRON MICROSCOPY IN 1963 BY NASS & NASS

IT WAS ISOLATED FROM YEAST MITOCHONDRIA

BY SCHATZ

IN 1981 THE MITOCHONDRIAL GENOME WAS COMPLETELY

SEQUENCED BY ANDERSON et al.

mtDNA IS MATERNALLY INHERITED [GILES ET AL 1980]

mtDNA IS A SEMI-AUTONOMOUS MOLECULE, WHICH DOES NOT

UNDERGO RECOMBINATION.

CIRCULAR MOLECULE OF 16569 BP LENGTH

37 GENES

13 CODING PROTEINS

2 rRNAS, 22 tRNAS

THE ONLY NON-CODING REGION IN THE MTDNA IS

SITUATED BETWEEN THE GENES CODING FOR

tRNA-PRO AND t-RNA-PHE.

IT IS ABOUT 1120bp IN HUMANS

MITOCHONDRIAL DNA MAP

THE CONTROL REGION IS HIGHLY STRUCTURED,

WITH A CONSERVED CENTRAL REGION (CCR)

FLANKED BY TWO HIGHLY DIVERGENT

PERIPHERAL DOMAINS.

IN HUMANS THE TWO PERIPHERAL REGIONS ARE

CALLED HYPER VARIABLE REGIONS ONE AND TWO (HVR-I

AND HVR-II).

THE CONTROL REGION IS RELATIVELY TOLERANT OF

HIGH MUTATION RATE,

THE MT GENOME IS INHERITED INTACT OVER

THOUSANDS OF GENERATIONS, WITHOUT THE

CONFOUNDING EFFECT OF CROSSOVER WITH A

PATERNAL CHROMOSOME.

THESE FEATURES OF mtDNA HAVE BEEN EXPLOITED FOR

EVOLUTIONARY AND POPULATION GENETIC STUDIES

MAKING IT A SUITABLE CANDIDATE FOR THE STUDY.

THIS PROJECT AIMS TO FIND GENOMIC DIVERSITY

WITHIN AND BETWEEN ENDOGAMOUS POPULATIONS BY

EVOLUTION USING A STANDARD DNA MARKER –mtDNA

ISOLATION OF DNA

QUANTIFICATION OF DNA

DILUTING THE DNA SAMPLES

AGAROSE GEL ELECTROPHORESIS

POLYMERASE CHAIN REACTION

PCR FOR 9bp

PCR Reaction Mixture Requirement

PCR BufferMgCl2

dNTPsPrimer APrimer BTaq PolymeraseDDWDNA (10ng/μl)

Volume(μl)

10.60.81.01.00.5

1.14

PCR Conditions

Steps

12345678

Conditions

950C for 5min950C for 1min550C for 1min720C for 1minGo to 2, 35 times720C for 5min40C for everEnd

THE PRODUCTS WERE THEN RESOLVED IN 6% POLYACRYLAMIDEGEL .

NO DELETIONS AND INSERTIONS WERE OBSERVED.

POLYMERASE CHAIN REACTION

HVR I PRIMER

PCR Reaction Mixture

Requirement Volume(μl)

PCR BufferMgCl2

dNTPsPrimer FPrimer RTaq PolymeraseDDWDNA (10ng/μl)

10.60.350.20.20.53.154

PCR Conditions

Steps Conditions

12345678

940C for 1min940C for 30sec600C for 45sec720C for 2 min30secGo to 2, 34 times720C for 7min40C for everEnd

SEQUENCING PCR

THESE PCR PRODUCTS ARE SEQUENCED IN ABI PRISM 3700 AUTOMATED DNA ANALYSER

Requirement

BigDye™Primer FDDWDNA (10ng/μl)

Volume (μl)

1.80.12.11

PCR Reaction Mixture PCR Conditions

Steps

123

4

Conditions

950C for 10sec500C for 5sec600C for4min, 30cycles40C for ever & end

THE SEQUENCES WERE ASSEMBLED IN AUTOMATED DNA SEQUENCER

ANALYSIS OF FLOURESCENT LABELLED DNA MOLECULES. THIS INSTRUMENT COMPRISES OF A ELECTROPHORETIC APPARATUS WITH A 5000 V POWER SUPPLY.

ARGON ION LASER.

CCD CAMERA.

MACINTOSH COMPUTER WITH SOFTWARE SUCH AS AUTO ASSEMBLER. THE SEQUENCES WERE ASSEMBLED AND COMPARED WITH ANDERSON mt DNA SEQUENCE AND MUTATION SITES WERE NOTED.

NOTE ALL THE MUTATION SITES AFTER ASSEMBLING THE DNA SEQUENCES WITH THE ANDERSON SEQUENCE .

MJ NETWORK ,THE NETWORK WAS DRAWN USING HVR 1 SEQUENCES THROUGH NETWORKING 3.0 VERSION SOFTWARE OF FLUXUS ENGINEERING.

A TOTAL OF 15 HAPLOTYPES WERE OBTAINED . OUT OF 15 ,10 ARE UNIQUE AND REST FORM COMMON SETS OF HAPLOTYPES.

MJ NET WORK

MEDIAN JOINING NETWORK OF CHENCHU TRIBE

NJ NET WORK

NEIGHBOUR JOINING TREE WAS CONSTRUCTED WITH THE DATA FROM 44 CHENCHU INDIVIDUALS WITH THE DATA FROM THE INDIVIDUALS OF OTHER INDIAN POPULATIONSUSING CLUSTAL X, ARLEQUIN ,PHYLIP SOFTWARES .

THE CHENCHU POPULATION HAS CLOSE RELATOION WITH DUNGRI BHILS ,DUNGRI GARASIAS, IRULA NILGIRIS

NJ NETWORK OF CHENCHU TRIBE