Biology Reference
In-Depth Information
80
DNA carried by the transducing particle of two minutes or bp,
and can give the distances between genetic markers A and B and that
between B and C.
AN EXAMPLE
Numerous three-point analysis experimental data are available in the
literature. A typical example is illustrated here. The three sets of four
replica plates of patches are shown in Figs. 3-7 to 3-9. These numbers of
patches are then converted to ratios given in Table 3-1 (Singer
et al.,
1965).
Table 3-1. Ratios from a three-point analysis experiment.
[A+B-C-] [A+B+C-] [A+B-C+] [A+B+C+] [A-B+C-] [A-B+C+] [A-B-C+]
{A+]
0.51
0.30
0.00
0.19
0.20
0.17
0.20
0.43
[B+]
0.00
0.14
0.43
[C+]
0.43
It is obvious from Table 3-1 that experimental errors are not avoidable. For
example, theoretically
[A+B+C-] / [A+] = [A+B+C-] / [B+],
but the experimental measured ratios are 0.30 and 0.20 respectively. It is for
this reason that least square fitting to the ten non-zero experimental data
points can give very accurate values of and
Initial estimations of
and
can be obtained from [A+B-C-] / [A+] and [A-B-C+] / [C+], i.e.
0.51 =
and
0.43 =
