180 likes | 266 Vues
Inference rules for supernetwork construction. Katharina Huber, School of Computing Sciences, University of East Anglia. gene2( ). gene1( ). gene2( ). gene1( ). gene2( ). gene1( ). gene2( ). gene1( ). gene2( ). gene1( ).
E N D
Inference rules for supernetwork construction Katharina Huber, School of Computing Sciences, University of East Anglia.
gene2( ) gene1( ) gene2( ) gene1( ) gene2( ) gene1( ) gene2( ) gene1( ) gene2( ) gene1( ) An ultimate goal
gene1( ) But, … ? gene1( ) gene2( ) gene1( ) gene1( ) gene2( ) gene2( ) gene2( )
gene1( ) gene1( ) gene1( ) gene1( ) gene1( ) Or, even worse ? gene2( ) gene2( ) gene2( ) gene2( )
gene1( ) gene1( ) gene1( ) gene1( ) gene1( ) We could, … ? gene2( ) gene2( ) gene2( ) gene2( )
gene1( ) gene1( ) gene1( ) gene1( ) gene1( ) or, … ? gene2( ) gene2( ) gene2( ) gene2( )
So far, .. • Z-closure supernetwork (Huson et al, 2004) • Q-imputation (Holland et al, 2007), Attractive but produce many splits Filtering approaches
Weak compatibility(Bandelt and Dress, 1992) A1 A1 A2 A2 A3 A3 One of intersections marked by a dot is empty!
Weak compatibility(Bandelt and Dress, 1992) A1 A1 A2 A2 A3 A3
Repeat until inference process stabilizes apply inference rule and add (if underlying condition is violated stop) Collection of partial splits Collection of partial splits remove partial splits that can get extended A|B extends C|D if either A C and B D or A D and B C.
Theorem (Gruenewald, Huber, Wu) Suppose is an irreducible collection of partial splits and is either the Y- or M- or M/Y-rule. Then any two closures of obtained via are the same. Irreducible: no split in extends another split in . Closure: if the underlying condition(s) is (are) never violated, the set of partial splits generated when inference process stabilizes, and otherwise.
S1 7 1 S2 6 2 5 S3 3 4 Circular collections of partial splits S1=123|4567 S2=23|45671 S3=345|6712 A collection of partial split is said to be displayed by a cycle if every split in can get extended to a full split such that the resulting split system is circular.
Theorem (Gruenewald, Huber, Wu) Suppose is an irreducible collection of partial splits. Then is displayed by a cycle C if and only if the closure of via M/Y is displayed by C. In that case the closure of via Y and the closure of via M is also displayed by C.
Rivera et al’s ring of lifeRivera et al, 2004 5 most probable phylogenetic trees from a study of 10 bacterial genomes from Rivera et al, 2004 in its early stages life was more like a network than a tree. How much does this result depend on the fact that trees were all on the same taxa set?
Z-closure supernetwork The ring of lifeRivera et al, 2004 M/Y-inference rules