Freiburg.bioinfo I.2008s.uebungsblatt04

1
Albert–Ludwigs–Universit¨ at Freiburg Fakult¨ at f ¨ ur Angewandte Wissenschaften Institut f ¨ ur Informatik Prof. Dr. Rolf Backofen http://www.bioinf.uni-freiburg.de Anke Busch [email protected] Exercise to the Lecture Bioinformatik I SS 2008 Exercise Sheet 4 – NEW until: 10.07.2008 Exercise 1 Find the best multiple alignment for sequences a, b and c using the method of Feng & Doolittle! For the pairwise alignment, use the algorithm of Needleman & Wunsch with the similarity function s(x, y)= 1 x = y 1 x = y The alignment tree is given by: {a,b} a b c {a,b,c} The sequences are: a = GCATG b = GGCAG c = CCTGA Exercise 2 Find the phylogenetic tree of the six sequences a,b,c,d ,e, and f using the hierarchical clustering method UPGMA! You are given the distance matrix D: D i, j = a b c d e f a 0 8 8 14 14 24 b 0 2 14 14 24 c 0 14 14 24 d 0 2 24 e 0 24 f 0

description

info

Transcript of Freiburg.bioinfo I.2008s.uebungsblatt04

  • AlbertLudwigsUniversitat FreiburgFakultat fur Angewandte WissenschaftenInstitut fur Informatik

    Prof. Dr. Rolf Backofenhttp://www.bioinf.uni-freiburg.de

    Anke [email protected]

    Exercise to the Lecture

    Bioinformatik ISS 2008

    Exercise Sheet 4 NEW

    until: 10.07.2008

    Exercise 1

    Find the best multiple alignment for sequences a,b and c using the method of Feng & Doolittle! For thepairwise alignment, use the algorithm of Needleman & Wunsch with the similarity function

    s(x,y) ={

    1 x = y1 x 6= y

    The alignment tree is given by:

    {a,b}

    a b c

    {a,b,c}

    The sequences are: a = GCATGb = GGCAGc = CCTGA

    Exercise 2

    Find the phylogenetic tree of the six sequences a,b,c,d,e, and f using the hierarchical clustering methodUPGMA! You are given the distance matrix D:

    Di, j =

    a b c d e fa 0 8 8 14 14 24b 0 2 14 14 24c 0 14 14 24d 0 2 24e 0 24f 0