Centromere Second Division Distance
Estimate gene-to-centromere distance as half the ordered-tetrad second-division percentage.
Description
Ordered tetrads can reveal second-division segregation associated with recombination between a gene and centromere.
Ordered tetrads can reveal second-division segregation associated with recombination between a gene and centromere. The simple distance estimate uses half the observed percentage.
Estimate gene-to-centromere distance as half the ordered-tetrad second-division percentage.
When to use Centromere Second Division Distance
Use this for the following task: Estimate gene-to-centromere distance as half the ordered-tetrad second-division percentage.
Prepare the observed records or explicit model parameters requested below. Keep probabilities as fractions and paired records aligned.
How to use Centromere Second Division Distance and understand its results
- Prepare the observed records or explicit model parameters requested below. Keep probabilities as fractions and paired records aligned.
- Enter secondDivisionTetrads, totalOrderedTetrads using the field table, then run the tool.
- Read secondDivisionPercent, centromereDistanceCm. Interpret flags, units, ordering and placeholder values using the rules below.
- Review any reported issue or failed check, correct the supplied values when appropriate, and verify the result in its intended context.
| Input field | Meaning | Value type and bounds | Requirement |
|---|---|---|---|
| secondDivisionTetrads | Second division tetrads | integer | Required |
| totalOrderedTetrads | Total ordered tetrads | integer | Required |
Supply nonnegative second-division counts bounded by a positive ordered-tetrad total. Compute percent and its half-distance.1
secondDivision%=100 SDS/total; distance cM=secondDivision%/2 This summarizes the declared operation. Units, indexing, inclusivity and exceptional cases are explained in the surrounding text.
| Output field | Meaning | Value type |
|---|---|---|
| secondDivisionPercent | Second division percent | number |
| centromereDistanceCm | Centromere distance cm | number |
{
"input": {
"secondDivisionTetrads": 20,
"totalOrderedTetrads": 100
},
"output": {
"secondDivisionPercent": 20,
"centromereDistanceCm": 10
}
}Limitations and assumptions
Tetrad classification is supplied and multiple-crossover corrections are excluded.
The tool evaluates supplied observations or a declared model. It does not establish the biological cause of an observed pattern. Malformed requests produce input errors. A successfully evaluated request can still contain false flags, empty result lists or a result outside the supplied threshold; those outcomes have the meanings stated above.
Alternative or Complementary methods
Choose Tetrad Segregation Tally for this operation: Tally unordered tetrad classes and recombinant-product fraction. For a complementary task, use Linkage Interval Map for this operation: Build additive genetic-map positions from ordered adjacent interval distances.
The implementation reference documents the exact calculation, supported input shapes and returned fields.
References
-
Centromere Second Division Distance — tool.io
Similar or alternative tools
- Tetrad Segregation Tally
Tally unordered tetrad classes and recombinant-product fraction.
- Linkage Interval Map
Build additive genetic-map positions from ordered adjacent interval distances.