A Genetic Linkage Map of Blood Clam (Tegillarca granosa) Based on Simple Sequence Repeat and Amplified Fragment Length Polymorphism Markers

ABSTRACT A genetic linkage map of the blood clam (Tegillarca granosa) was constructed based on simple sequence repeat (SSR) and amplified fragment length polymorphism (AFLP) markers. An F1 family consisting of 109 individuals was created using the “two-way pseudo-testcross” mapping strategy. A total of 568 polymorphic markers, including 32 SSRs and 534 AFLPs, were used in the linkage mapping. The female linkage map consisted of 250 marker loci (15 SSR and 255 AFLP), which formed 18 linkage groups with an average marker space of 7.15 cM; they spanned a total length of 1,649.33 cM, covering 84.49% of the estimated genome size. The male map consisted of 290 marker loci (14 SSR and 276 AFLP), which mapped to 22 linkage groups with an average marker spacing of 5.56 cM. They spanned a total length of 1,485.09 cM, covering 84.43% of the estimated genome size. This map is the first genetic linkage map in the blood clam and provides a basis for mapping quantitative trait loci and for breeding applications.