what is the total number of genes that are found on chromosome 20 (human)?
Value
527
class entity
biology.gene m.02kwgm0
biology.gene biology.chromosome
Gene Chromosome 20 (human)
count none
biology.gene.chromosome
Chromosome
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#> PREFIX : <http://rdf.freebase.com/ns/> 
SELECT (COUNT(?x0) AS ?value) WHERE {
SELECT DISTINCT ?x0  WHERE { 
?x0 :type.object.type :biology.gene . 
VALUES ?x1 { :m.02kwgm0 } 
?x0 :biology.gene.chromosome ?x1 . 
FILTER ( ?x0 != ?x1  )
}
}
(COUNT (AND biology.gene (JOIN biology.gene.chromosome m.02kwgm0)))