Rym Kefi

50 %
50 %
Information about Rym Kefi

Published on January 5, 2008

Author: Me_I

Source: authorstream.com

Human population phylogenetic studies using mithochondrial DNA :  Human population phylogenetic studies using mithochondrial DNA Dr Rym KEFI MIGOD- Institut Pasteur -Tunis Slide2:  Plan: I- Introduction II- Example: Phylogenetic and Neandertal enigma. II- Example I: Mitochondrial DNA diversity of the prehistoric population from Taforalt (12,000 years- Morocco). Slide3:  The main aim of Human population genetics is to find answers concerning: Introduction Differentiation in single population (Bertranpetit et al 1995; Ann Hum Genet) Slide4:  the migration patterns in certain geographic areas. Slide5:  human evolution, and the spread of modern humans (Richards et al 1996, Am J Hum Genet ) Slide6:  Mitochondrial DNA an important tool for Human population genetics Slide7:  The studies of mtDNA polymorphism in human populations were based: initially on restriction enzyme (RFLP) analysis : Low resolution restriction and high resolution restriction mapping (Horai et al 1984, Johnson et al 1983, Horai et al 1984, Cann et al 1987, Torroni et al 1993 ) , Brown and Wallace in 1970: Pioneers in mtDNA investigation Mitochondrial DNA Studies history: Slide8:  on combined method using sequence analysis and restriction mapping (Bertranpetit et al 1995, Vigilant et al 1991, Richards et al 1996, Richards et al 1998, Macaulay 1999, Torroni et al 2001, Maca-Meyer et al 2001, Salas et al 2002) on sequence analysis of the mtDNA control region Slide9:  Mitochondrial Eve Cann et al; Nature 1987 147 individuals from five geographic populations: Europe, Africa, Asia, Australia, New Guinea have been analysed by high-resolution restriction mapping Slide10:  Different mtDNA lineages have been diverged from an ancestral women originated in Africa. Mitochondrial Eve Slide11:  RFLPs studies of mtDNA from a wide range of Human populations have revealed a number of stable polymorphic sites in the mtDNA coding region . Mutations observed in both mtDNA coding region and control region in modern human populations have occurred on these pre-existing haplogroups Define the individual mtDNA type or haplotypes Define related groups of mtDNA called haplogroups Slide12:  Alignment of sequences with mtDNA reference (CRS) using “Blast 2 sequences” Haplotype and Haplogroup + RFLP analysis Slide13:  Examples : Individual 1: Slide14:  Mitochondrial haplogroups Slide15:  The phylogenetic relationships between haplotypes were inferred in the first studies by Maximum parsimony tree Then by Neighbor- joining trees Later by Median joining network. Trees were based on distance data calculated from Nucleotide sequence or RFLPs data or Nucleotide sequence combined with RFLPs data. Slide16:  Macaulay et al, 1999; , Am J Hum Genet, Slide17:  Dr Rym KEFI and Dr Eliane BERAUD-COLOMB U600 INSERM-FRE2059 CNRS Laboratoire d'Immunologie, Hôpital de Sainte-Marguerite- Marseille- France Example I: Mitochondrial DNA diversity of the prehistoric population from Taforalt (12,000 years- Morocco). Slide18:  Knowledge of the settlement of Northern Africa region Study of molecular diversity of modern Human populations Study of archaeological specimens and their environment Slide19:  Anthropologic data Transition from Homo erectus towards Homo sapiens archaic Slide20:  Ibero-Maurusian man Ibero-Maurusian industry Slide22:  Ibero-maurusian man 1-Europian origin? (Vallois 1969, Ferembach 1985) 2- Near East origin ? (Vandermeersch 1978) 4- North African origin ? (Camps 1989, Dutour 1995) 3- Subsaharian origin? (Ferembach 1976) Origins ??? Slide23:  Ancestral indigenous component: U6- (Paleolithic: 45.000 years) Eurasiatic component: T, H, U, J…(Neolithic?: 9000 years) Sub-Saharan component : L (Historic?) Former studies using Mitochondrial DNA (Côrte-Real et al. 1996; Rando et al. 1998; Comas et al. 2000; Brakez et al. 2001; Esteban et al. 2004…) showed that the genetic structure of North Africa is composed of 3 components: Genetic data Slide24:  to contribute to the knowledge of North Africa settlement We proposed to analyse the mitochondrial DNA diversity of the prehistoric population from Taforalt (13,000 years BP- Morocco). Aim: Slide25:  The cave of Taforalt in Morocco The cave of Taforalt is Located at 55 km in the North-West of Oujda Slide26:  Ancient DNA was extracted from 31 bone remains from Taforalt Phenol/Chloroforme Extraction Dissolution of bone powders ADN Hypervariable segment 1 (HVS1) of control region (D-Loop) was amplified by PCR and sequenced (R. Kefi et al; C.R.Palévol 2003) Slide27:  Mitochondrial DNA diversity of Taforalt population Genetic structure of Taforalt: Eurasiatic Component : H, U, JT, V: 90,5% North African component: U6: 9,5% In modern Human population, JT is presents only in: 1,6% Berbers from the North of Morocco 1,8% of Sicilians, 1,6% of Italians. Slide28:  The genetic inheritance of Taforalt population (12,000 years) is composed of: Eurasiatic component (J/T, H, U et V) North African component (U6). Similarities between Taforalt and Moroccan populations (Berbers from the North of Morocco) Underline a genetic continuity Slide29:  Ibero-maurusian Origin 4- local origin ? (Camps 1989, Dutour 1995) 3- Sub-Saharan origin? (Ferembach 1976) 1-European origin? (Vallois 1969, Ferembach 1985) 2- Near East origin ? (Vandermeersch 1978) Kefi et al 2005 Anthropologie ; Xliii/1: 55-64 Slide30:  Phylogenetic and Neandertal enigma Example 2: Neandertal lived in Europe and west Asia between 150.000 and 30.000 years (Grimaud–Hervé et al 2001, Klein et al 2003) Neandertal has specific morphological characters (lengthened Cranium, presence of Taurus on orbits , big cranial capacity...) which distinguish him from the anatomically modern man Neandertal coexisted with anatomically modern man, before disappearing 30.000 years ago Slide31:  Many interrogations about the role of Neandertal in the Human evolution. Neandertal is he our ancestor? Did he contribute in our genetic inheritance? or did he disappear without leaving any trace in our genome? Homo Sapiens sapiens Homo neandertalensis Did he belongs to another species? Slide32:  Krings and collaborators (Krings et al. 1997, Cell) studied for the first time ancient DNA extracted from Neandertal humerus. Neandertal was discovered in West Germany. 377 bp Neandertal sequence was aligned with CRS (Cambridge reference sequence). The alignment shows 27 differences (24 transitions, 2 tranversions, 1 deletion) Ancient bone DNA Slide33:  Neandertal sequence was compared to 994 mt DNA sequences from the five continents. The difference between the Modern Man and Neandertal is higher than the intra specific diversity in Modern Human specie. Slide34:  indicates that Neandertal position is distinct from the group including all the Modern Human sequences. NJ tree constructed with 986 modern Human mt DNA sequences, 16 chimpanzee sequences and Neandertal sequence Slide35:  These results show that Neandertal is not the ancestor of the modern Human. Homo sapiens sapiens and Homo neandertalensis constitute two distinct species. Homo sapiens sapiens Homo neandertalensis Slide36:  Marseille

Add a comment

Related presentations

Related pages

Rym Kefi Profiles | Facebook

View the profiles of people named Rym Kefi. Join Facebook to connect with Rym Kefi and others you may know. Facebook gives people the power to share and...
Read more

Top 5 Rym Kefi profiles | LinkedIn

View the profiles of professionals named Rym Kefi on LinkedIn. There are 5 professionals named Rym Kefi, who use LinkedIn to exchange information, ideas ...
Read more

Rym Kefi | Global Young Academy

Dr Rym KEFI is an Assitant Professor in Pasteur Institute of Tunis. She obtained her bachelor degree with honours in Biology at the University of Tunis on ...
Read more

Rym Kéfi | Facebook

Rym Kéfi is on Facebook. Join Facebook to connect with Rym Kéfi and others you may know. Facebook gives people the power to share and makes the world...
Read more

Rym Kefi | Papers - Academia.edu

Rym Kefi studies Lactic Acid Bacteria, Snakes, and Biologie. Log In; Sign Up; About; Papers 21; CV; Add Social Profiles (Facebook, Twitter, etc.) Rym Kefi.
Read more

Rym BEL KEFI | LinkedIn

View Rym BEL KEFI’S professional profile on LinkedIn. LinkedIn is the world's largest business network, helping professionals like Rym BEL KEFI discover ...
Read more

Publications Authored by Rym Kefi - pubfacts.com

Are you Rym Kefi? Claim your profile, edit publications, add additional information:
Read more

RYM EL KEFI - Google+ - plus.google.com

RYM EL KEFI hasn't shared anything on this page with you.
Read more

Finally!! – Rym Kefi(2014) – Origin of mtDNA H ...

Phylogeny and genetic structure of Tunisian populations and their position within Mediterranean - Rym Kefi 2014 Compared to 4206 mtDNA sequences from ...
Read more

ATEH: Conférence de Rym Kefi_1 - YouTube

Première conférence des "Rendez vous de l'Association Tunisienne des Etudes Historiques" sur le thème "Être tunisien". "Les analyses ADN ...
Read more