##"A few people in the field of genetics are using dot to draw "marriage node diagram"  pedigree drawings.  Here is one I have done of a test pedigree from the FTREE pedigree drawing package (Lion Share was a racehorse)." Contributed by David Duffy.

##Command to get the layout: "dot -Tpng thisfile > thisfile.png"

digraph Ped_Lion_Share           {
# page = "8.2677165,11.692913" ;
ratio = "auto" ;
mincross = 2.0 ;
label = "Pedigree Lion_Share" ;

"001" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"002" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"003" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"004" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"005" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"006" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"007" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"009" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"014" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"015" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"016" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"ZZ01" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"ZZ02" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"017" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"012" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"008" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"011" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"013" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"010" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"023" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"020" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"021" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"018" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"025" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"019" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"022" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"024" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"027" [shape=circle  , regular=1,style=filled,fillcolor=white   ] ;
"026" [shape=box     , regular=1,style=filled,fillcolor=white   ] ;
"028" [shape=box     , regular=1,style=filled,fillcolor=grey    ] ;
"marr0001" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"001" -> "marr0001" [dir=none,weight=1] ;
"007" -> "marr0001" [dir=none,weight=1] ;
"marr0001" -> "017" [dir=none, weight=2] ;
"marr0002" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"001" -> "marr0002" [dir=none,weight=1] ;
"ZZ02" -> "marr0002" [dir=none,weight=1] ;
"marr0002" -> "012" [dir=none, weight=2] ;
"marr0003" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"002" -> "marr0003" [dir=none,weight=1] ;
"003" -> "marr0003" [dir=none,weight=1] ;
"marr0003" -> "008" [dir=none, weight=2] ;
"marr0004" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"002" -> "marr0004" [dir=none,weight=1] ;
"006" -> "marr0004" [dir=none,weight=1] ;
"marr0004" -> "011" [dir=none, weight=2] ;
"marr0005" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"002" -> "marr0005" [dir=none,weight=1] ;
"ZZ01" -> "marr0005" [dir=none,weight=1] ;
"marr0005" -> "013" [dir=none, weight=2] ;
"marr0006" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"004" -> "marr0006" [dir=none,weight=1] ;
"009" -> "marr0006" [dir=none,weight=1] ;
"marr0006" -> "010" [dir=none, weight=2] ;
"marr0007" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"005" -> "marr0007" [dir=none,weight=1] ;
"015" -> "marr0007" [dir=none,weight=1] ;
"marr0007" -> "023" [dir=none, weight=2] ;
"marr0008" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"005" -> "marr0008" [dir=none,weight=1] ;
"016" -> "marr0008" [dir=none,weight=1] ;
"marr0008" -> "020" [dir=none, weight=2] ;
"marr0009" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"005" -> "marr0009" [dir=none,weight=1] ;
"012" -> "marr0009" [dir=none,weight=1] ;
"marr0009" -> "021" [dir=none, weight=2] ;
"marr0010" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"008" -> "marr0010" [dir=none,weight=1] ;
"017" -> "marr0010" [dir=none,weight=1] ;
"marr0010" -> "018" [dir=none, weight=2] ;
"marr0011" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"011" -> "marr0011" [dir=none,weight=1] ;
"023" -> "marr0011" [dir=none,weight=1] ;
"marr0011" -> "025" [dir=none, weight=2] ;
"marr0012" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"013" -> "marr0012" [dir=none,weight=1] ;
"014" -> "marr0012" [dir=none,weight=1] ;
"marr0012" -> "019" [dir=none, weight=2] ;
"marr0013" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"010" -> "marr0013" [dir=none,weight=1] ;
"021" -> "marr0013" [dir=none,weight=1] ;
"marr0013" -> "022" [dir=none, weight=2] ;
"marr0014" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"019" -> "marr0014" [dir=none,weight=1] ;
"020" -> "marr0014" [dir=none,weight=1] ;
"marr0014" -> "024" [dir=none, weight=2] ;
"marr0015" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"022" -> "marr0015" [dir=none,weight=1] ;
"025" -> "marr0015" [dir=none,weight=1] ;
"marr0015" -> "027" [dir=none, weight=2] ;
"marr0016" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"024" -> "marr0016" [dir=none,weight=1] ;
"018" -> "marr0016" [dir=none,weight=1] ;
"marr0016" -> "026" [dir=none, weight=2] ;
"marr0017" [shape=diamond,style=filled,label="",height=.1,width=.1] ;
"026" -> "marr0017" [dir=none,weight=1] ;
"027" -> "marr0017" [dir=none,weight=1] ;
"marr0017" -> "028" [dir=none, weight=2] ;
}
