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Localized negative interference and its bearing on models of gene recombination

Published online by Cambridge University Press:  14 April 2009

R. H. Pritchard
R. H. Pritchard
Affiliation:
Department of Genetics, The University, Glasgow
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In the analysis of recombination in Aspergillus nidulans coincidence values of about 1 are found in 3-point tests using markers more than a few map units apart. In comparable tests in which the marked intervals were very short (0·1 map unit or less), coincidence values of over 100 had been found. To account for this difference it was proposed that a necessary condition for recombination, termed ‘effective pairing’, was realized at any particular point on the chromosome in only a small fraction of a population of cells at meiosis. It was supposed that when effective pairing occurred it extended over a very short segment of the chromosome and that the probability of recombination in the effectively paired segment was high, i.e. about 1. Coincidence values greater than unity would be a necessary consequence of such a situation provided the intervals in question had a total length not much greater than that of effective pairing segments.

The experiments described in this paper were undertaken in an attempt to measure the mean length of effectively paired segments, their distribution, and the frequency of exchange within them. The data suggest a mean length of about 0·4 map unit, a mean exchange frequency of about 0·6, and a distribution which is variable, perhaps random.

The occurrence of localized negative interference suggests a way in which a number of difficulties encountered in relating the experimental evidence concerning the time and mechanism of recombination with the cytological evidence concerning the sequence of events at meiosis might be resolved. The data indicate that the frequency of recombination between linked loci is a measure principally of the frequency of effective pairing between them. If effective pairing is synonymous with homologous contact between chromosomes, and evidence is presented which suggests this may be the case, it becomes possible to construct a simple model which is compatible with the view that recombination takes place before chromosomes are paired, in the cytologically observable sense (i.e. before zygotene), at meiosis.

The recombination events occurring within effectively paired regions are generally, although possibly not exclusively, reciprocal. Non-reciprocal recombinants have been encountered in Aspergillus and other organisms, characterized by the occurrence of 3:1 ratios in tetrads. On the basis of evidence currently available it does not seem necessary to invoke a special mechanism of recombination, distinct from crossing over, to account for the formation of non-reciprocal recombinaiits. A single mechanism of recombination of the copy-choice type which, although primarily a reciprocal process, is nevertheless not necessarily exactly so or always so in detail, will account for the observed results.

Type
Research Article
Information
Genetics Research , Volume 1 , Issue 1 , February 1960 , pp. 1 - 24
Copyright
Copyright © Cambridge University Press 1960

References

REFERENCES

Beadle, G. W. (1957). The role of the nucleus in heredity. The Chemical Basis of Heredity. Baltimore: Johns Hopkins Press. Pp. 3–22.Google Scholar
Calef, E. (1957). Effect on linkage maps of selection of crossovers between closely linked markers. Heredity, 11, 265–279.CrossRefGoogle Scholar
Case, M. E. & Giles, N. H. (1958). Evidence from tetrad analysis for both normal and abnormal recombination between allelic mutants in Neurospora crassa. Proc. Nat. Acad. Sci., Wash., 44, 378–390.CrossRefGoogle Scholar
Cavalli-Sforza, L. L. & Jinks, J. L. (1956). Studies on the genetic system of Escherichia coli K-12. J. Genet. 54, 87–112.CrossRefGoogle Scholar
Chase, M. & Doermann, A. H. (1958). High negative interference over short segments of the genetic structure of bacteriophage T4. Genetics, 43, 332–353.CrossRefGoogle ScholarPubMed
Chovnick, A. (1958). Aberrant segregation and pseudoallelism at the garnet locus in Drosophila melanogaster. Proc. Nat. Acad. Sci., Wash., 44, 333–337.CrossRefGoogle ScholarPubMed
Darlington, C. D. (1934). The origin and behaviour of chiasmata. VII. Zea Mays. Z. indukt. Abstamm.-u. VererbLehre, 67, 96–114.Google Scholar
Darlington, C. D. (1935). The time, place and action of crossing-over. J. Genet. 31, 185–212.CrossRefGoogle Scholar
Darlington, C. D. (1941). The causal sequence of meiosis. II Contact points and crossing-over potential in a triploid Fritillaria. J. Genet. 41, 35–48.CrossRefGoogle Scholar
Demerec, M. (1928). Mutable characters of Drosophila virilis. I. Reddish-alpha body character. Genetics, 13, 359–388.CrossRefGoogle ScholarPubMed
De Serres, F. J. (1958). Recombination and interference in the ad-3 region of Neurospora crassa. Cold Spr. Harb. Symp. quant. Biol. 23, 111–118.CrossRefGoogle ScholarPubMed
Elliott, C. G. (1959). In the press.Google Scholar
Emerson, S. (1956). Notes on the identification of different causes of aberrant tetrad ratios in Saccharomyces. C. R. Lab. Carlsberg, 26, 71–86.Google Scholar
Freese, E. (1957 a). The correlation effect for a histidine locus of Neurospora crassa. Genetics, 42, 671–684.CrossRefGoogle ScholarPubMed
Freese, E. (1957 b). Über die Feinstruktur des genoms im Bereich eines pab Locus von Neurospora crassa. Z. indukt. Abstamm.- u. VererbLehre, 88, 388–406.Google ScholarPubMed
Giles, N. H. (1951). Studies on the mechanism of reversion in biochemical mutants of Neurospora crassa. Cold Spr. Harb. Symp. quant. Biol. 16, 283–313.CrossRefGoogle ScholarPubMed
Giles, N. H. (1955). Forward and backward mutation at specific loci in Neurospora. Brook-haven Symp. in Biol., 8, 103–125.Google Scholar
Giles, N. H., De Serres, F. J. & Barbour, E. (1957). Studies with purple adenine mutants of Neurospora crassa. II. Tetrad analysis from a cross of an ad-3A mutant with an ad-3B mutant. Genetics, 42, 608–617.CrossRefGoogle Scholar
Glass, B. (1957). A summary of the Symposium on The Chemical Basis of Heredity. Baltimore: Johns Hopkins Press. Pp. 257–834.Google Scholar
Green, M. M. (1954). Pseudo-allelism at the vermilion locus in Drosophila melanogaster. Proc. Nat. Acad. Sci., Wash., 40, 92–99.CrossRefGoogle ScholarPubMed
Green, M. M. & Green, K. C. (1949). Crossing over between alleles at the lozenge locus in Drosophila melanogaster. Proc. Nat. Acad. Sci., Wash., 35, 586–591.CrossRefGoogle ScholarPubMed
Haldane, J. B. S. (1919). The combination of linkage values, and the calculation of distances between loci of linked factors. J. Genet., 8, 299–309.Google Scholar
Hexter, W. M. (1958). On the nature of the garnet locus in Drosophila melanogaster. Proc. Nat. Acad. Sci., Wash., 44, 768–771.CrossRefGoogle ScholarPubMed
KäFer, E. (1958). An 8-chromosome map of Aspergillus nidulans. Advanc. Genet. 9, 105–145.CrossRefGoogle ScholarPubMed
Lederberg, J. (1955). Recombination mechanisms in bacteria. J. cell. comp. Physiol. 45 (Suppl. 2), 75–107.CrossRefGoogle ScholarPubMed
Leupold, U. (1958). Studies on recombination in Schizosaccharomyces pombe. Cold Spr. Harb. Symp. quant. Biol. 23, 161–170.CrossRefGoogle ScholarPubMed
Lewis, E. B. (1945). The relation of repeats to position effect in Drosophila melanogaster. Genetics, 30, 137–166.CrossRefGoogle ScholarPubMed
Lewis, E. B. (1952). The pseudoallelism of white and apricot in Drosophila melanogaster. Proc. Nat. Acad. Sci., Wash., 38, 953–961.CrossRefGoogle ScholarPubMed
Lindegren, C. C. (1955). Non-Mendelian segregation in a single tetrad of Saccharomyces ascribed to gene conversion. Science, 121, 605–607.CrossRefGoogle Scholar
Mackendrick, M. E. & Pontecorvo, G. (1952). Crossing over between alleles at the w locus in Drosophila melanogaster. Experientia., 8, 390.CrossRefGoogle Scholar
Mitchell, H. K. (1957). Crossing over and gene conversion in Neurospora. The Chemical Basis of Heredity. Baltimore: Johns Hopkins Press. Pp. 94–113.Google Scholar
Mitchell, M. B. (1955 a). Aberrant recombination of pyridoxin mutants of Neurospora. Proc. Nat. Acad. Sci., Wash., 41, 215–220.CrossRefGoogle ScholarPubMed
Mitchell, M. B. (1955 b). Further evidence of aberrant recombination in Neurospora. Proc. Nat. Acad. Sci., Wash., 41, 935–937.CrossRefGoogle ScholarPubMed
Mitchell, M. B. (1956). A consideration of aberrant recombination in Neurospora. C. R. Lab. Carlsberg, 26, 285–298.Google Scholar
Pontecorvo, G. (1958). Trends in Genetic Analysis. New York: Columbia University Press.Google Scholar
Pontecorvo, G. & KäFer, E. (1958). Genetic analysis based on mitotic recombination. Advanc. Genet. 9, 71–104.CrossRefGoogle ScholarPubMed
Pontecorvo, G. & Roper, J. A. (1956). Resolving power of genetic analysis. Nature, Lond., 178, 83–84.CrossRefGoogle ScholarPubMed
Pontecorvo, G., Roper, J. A., Hemmons, L. M., Macdonald, K. D. & Bufton, A. W. J. (1953). The genetics of Aspergillus nidulans. Advanc. Genet. 5, 141–238.CrossRefGoogle ScholarPubMed
Pritchard, R. H. (1955). The linear arrangement of a series of alleles in Aspergillus nidulans. Heredity, 9, 343–371.CrossRefGoogle Scholar
Roman, H. (1956). Studies of gene mutation in Saccharomyces. Cold Spr. Harb. Symp. quant. Biol. 21, 175–185.CrossRefGoogle ScholarPubMed
Roper, J. A. (1950). A search for linkage between genes determining vitamin requirements. Nature, Lond., 166, 956.CrossRefGoogle Scholar
Roper, J. A. & Pritchard, R. H. (1955). The recovery of the reciprocal products of mitotic crossing over. Nature, Lond., 175, 639.CrossRefGoogle Scholar
Rothfels, K. H. (1952). Gene linearity and negative interference in crosses of Escherichia coli. Genetics, 37, 297–311.CrossRefGoogle ScholarPubMed
Schultz, J. & Redfield, H. (1951). Interchromosomal effect on crossing over in Drosophila. Cold Spr. Harb. Symp. quant. Biol. 16, 175–197.CrossRefGoogle ScholarPubMed
Spurway, H. & Philip, U. (1952). Genetics and cytology of Drosophila subobscura. VII. Abnormal gene arrangements in element A. J. Genet. 51, 198–215.CrossRefGoogle Scholar
St.Lawrence, P. (1956). The q locus of Neurospora crassa. Proc. Nat. Acad. Sci., Wash., 42, 189–194.CrossRefGoogle Scholar
Streisinger, G. & Franklin, N. C. (1956). Mutation and recombination at the host range genetic region of phage T2. Cold Spr. Harb. Symp. quant. Biol., 21, 103–111.CrossRefGoogle ScholarPubMed
Strickland, W. N. (1958 a). Abnormal tetrads in Aspergillus nidulans. Proc. roy. Soc. B, 148, 533–542.Google ScholarPubMed
Strickland, W. N. (1958 b). An analysis of interference in Aspergillus nidulans. Proc. roy. Soc. B, 149, 82–101.Google ScholarPubMed
Sturtevant, A. H. (1951). A map of the fourth chromosome of Drosophila melanogaster, based on crossing over in triploid females. Proc. Nat. Acad. Sci., Wash., 37, 405–407.CrossRefGoogle ScholarPubMed
Sturtevant, A. H. (1955). Evaluation of recombination theory. J. cell. comp. Physiol. 45 (Suppl. 2), 237–242.CrossRefGoogle ScholarPubMed
Taylor, J. H. (1957). The time and mode of duplication of chromosomes. Amer. Nat. 91, 209–221.CrossRefGoogle Scholar
Upcott, M. (1935). The cytology of triploid and tetraploid Lycopersicum esculentum. J. Genet. 31, 1–19.CrossRefGoogle Scholar
Weinstein, A. (1918). Coincidence of crossing over in Drosophila melanogaster (ampelophila). Genetics, 3, 135–172.CrossRefGoogle ScholarPubMed