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Y D Tan

Publications and source records attributed to Y D Tan.

5 recordsLinked to original sources
PubMed2001

An amplified fragment length polymorphism map of the silkworm.

The silkworm (Bombyx mori L.) is a lepidopteran insect with a long history of significant agricultural value. We have constructed the first amplified fragment length polymorphism (AFLP) genetic linkage map of the silkworm B. mori at a LOD score of 2.5. The mapping AFLP markers were genotyped in 47 progeny from a backcross population of the cross no. 782 x od100. A total of 1248 (60.7%) polymorphic AFLP markers were detected with 35 PstI/TaqI primer combinations. Each of the primer combinations generated an average of 35.7 polymorphic AFLP markers. A total of 545 (44%) polymorphic markers are consistent with the expected segregation ratio of 1:1 at the significance level of P = 0.05. Of the 545 polymorphic markers, 356 were assigned to 30 linkage groups. The number of markers on linkage groups ranged from 4 to 36. There were 21 major linkage groups with 7-36 markers and 9 relatively small linkage groups with 4-6 markers. The 30 linkage groups varied in length from 37.4 to 691.0 cM. The total length of this AFLP linkage map was 6512 cM. Genetic distances between two neighboring markers on the same linkage group ranged from 0.2 to 47 cM with an average of 18.2 cM. The sex-linked gene od was located between the markers P1T3B40 and P3T3B27 at the end of group 3, indicating that AFLP linkage group 3 was the Z (sex) chromosome. This work provides an essential basic map for constructing a denser linkage map and for mapping genes underlying agronomically important traits in the silkworm B. mori L.

Animals↗
PubMed2001

[A new method for constructing linkage maps of molecular markers: three-point selfcross method].

The method for constructing linkage maps has almost been so far the three-point testcross in higher organisms. This method is, however, considerably limited to a requirement of a parent or line with three recessive genes that can be obtained by only cross breeding. In this paper, the three-point selfcross method for mapping was proposed. This method can also provide us with informations of mapping as the same as the three-point testcross method. However, the three-point selfcross method does not have any limitation of requiring a parent with three recessive genes. It was theoretically proved that this method could be used to map molecular marker loci in small sample of F2 population. Exactly to test both the methods for mapping, Fisher information content was applied to prove that the three-point selfcross method is powerful for mapping. Further to test this method, data of the first 6 loci were chosen from 12 RFLP loci detected in 333 F2 individuals in SAMPLE. RAW file in MAPMAKER/EXP version 3.0 that Lander et al. (1987) provided. The result showed that, like MAPMAKER program, the three-point selfcross method is powerful to detect linkage relationship among loci, to order them on linkage groups and to calculate distances between nearest neighbor loci. Besides, this method could provide us with the other information of map such as the positive or negative interference and couple or repulsion configuration.

Chromosome Mapping↗