A single IGF1 allele is a major determinant of small size in dogs.
The domestic dog exhibits greater diversity in body size than any other terrestrial vertebrate. We used a strategy that exploits the breed structure of dogs to investigate the genetic basis of size. First, through a genome-wide scan, we identified a major quantitative trait locus (QTL) on chromosome 15 influencing size variation within a single breed. Second, we examined genetic variation in the 15-megabase interval surrounding the QTL in small and giant breeds and found marked evidence for a selective sweep spanning a single gene (IGF1), encoding insulin-like growth factor 1. A single IGF1 single-nucleotide polymorphism haplotype is common to all small breeds and nearly absent from giant breeds, suggesting that the same causal sequence variant is a major contributor to body size in all small dogs.
Sutter
Nathan B
NB
National Human Genome Research Institute, Building 50, Room 5349, 50 South Drive MSC 8000, Bethesda, MD 20892-8000, USA.
Bustamante
Carlos D
CD
Chase
Kevin
K
Gray
Melissa M
MM
Zhao
Keyan
K
Zhu
Lan
L
Padhukasahasram
Badri
B
Karlins
Eric
E
Davis
Sean
S
Jones
Paul G
PG
Quignon
Pascale
P
Johnson
Gary S
GS
Parker
Heidi G
HG
Fretwell
Neale
N
Mosher
Dana S
DS
Lawler
Dennis F
DF
Satyaraj
Ebenezer
E
Nordborg
Magnus
M
Lark
K Gordon
KG
Wayne
Robert K
RK
Ostrander
Elaine A
EA
D000483:Alleles; D000818:Animals; D049628:Body Size / Q000235:genetics; D001947:Breeding; D004285:Dogs / Q000033:anatomy & histology* / Q000235:genetics*; D005091:Exons; D014644:Genetic Variation; D005838:Genotype; D006239:Haplotypes; D006579:Heterozygote; D007334:Insulin-Like Growth Factor I / Q000235:genetics* / Q000378:metabolism; D007438:Introns; D009154:Mutation; D020641:Polymorphism, Single Nucleotide; D040641:Quantitative Trait Loci; D012641:Selection, Genetic; D017422:Sequence Analysis, DNA
D007334:Insulin-Like Growth Factor I