SGD Help: Historical Genetic Mapping Data
Historical Genetic Mapping Data is included in three separate places in SGD: the Genetic Mapping Data page is a listing of all the genetic crosses submitted to SGD for a particular gene. Both tetrad and centromere segregation experiments are included, and details of these experiments can be accessed from the Genetic Mapping Data table. The Tetrad Data page summarizes the results of all of the tetrad data submitted to SGD for a pair of genetic markers; the Centromere Segregation Data page summarizes the results of all of the Centromere Segregation Data submitted to SGD for a particular locus.
Contents
Genetic Mapping Data
The Genetic Mapping Data can be accessed from links on the Physical and Genetics Maps, and the Genetic Maps, pages of the Historical Data section in the Community pull down. Clicking on the link "Two-point Genetic Mapping Data" brings up a search page where you can enter your gene of interest; the resulting page shows the Genetic Mapping Data table.
Genetic Mapping Data table
The Genetic Mapping Data table lists the following information:
| Markers used in the cross | the markers used in the cross are listed in the Locus #1 and Locus #2 columns. Click on the gene names to view their Locus pages. |
| # of Experiments | number of mapping experiments done for each pair of markers. Click on the number to view the detailed data from each of the experiments. |
| Average Distance | the average distance, in centimorgans, calculated from all the distances from the mapping experiments listed here. |
| Genetic Map Distance | the distance calculated from the Genetic Map Edition 12 (Cherry JM, Ball C, Weng S, Juvik G, Schmidt R, Adler C, Dunn B, Dwight S, Riles L, Mortimer RK, Botstein D. Nature 387(6632S):67-73 (1997)). |
The Genetic Mapping Data can be downloaded in a tab-delimited format via the Download Data link on the page.
Tetrad Data
Tetrad data for a gene is accessed by clicking on the number in the "# of Experiments" column of the Genetic Mapping Data table.
The Tetrad Data table
The Tetrad Data table lists the following information. Below the table are any notes about either (or both) of the genetic markers.
| Cross | the name of the experiment/cross; consists of the marker allele names used in the cross. |
| Parental Ditype | the number of tetrads that were parental ditypes. |
| Nonparental Ditype | the number of tetrads that were nonparental ditypes. |
| Tetratype | the number of tetrads that were tetratypes. |
| Distance | the genetic distance, in centimorgans, calculated from the number of parental ditypes, nonparental ditypes, and tetratypes. |
| Distance Standard Error | the standard error of the calculated distance. |
| Interference | the interference in the cross. |
| Interference Standard Error | the standard error of the calculated interference. |
| Notes/References | the notes and references relevant to the cross. The numbers link to the corresponding note or reference at the bottom of the page. |
Tetrad Data can be downloaded in a tab-delimited format via the Download Data link on the page.
Centromere Segregation Data
Centromere segregation data is accessed by clicking on the number in the "# of Experiments" column of the Genetic Mapping Data table.
The Centromere Segregation Data Table
The Centromere Segregation Data Table lists the following information. Below the table are any notes about the genetic markers.
| Cross | the name of the experiment/cross; consists of the marker allele names used in the cross. |
| First Division | number of first division segregants. |
| Second Division | number of second division segregants. |
| Distance | the genetic distance, in centimorgans, calculated from the number of first division and second division segregants. |
| Distance Standard Error | the standard error of the calculated distance. |
| Interference | the interference in the cross. |
| Interference Standard Error | the standard error of the calculated interference |
| Notes/References | the notes and references relevant to the cross. The numbers link to the corresponding note or reference at the bottom of the page. |
Centromere Segregation Data can be downloaded in a tab-delimited format via the Download Data link on the page.


