A. NOTICE AND ANNOUCEMENT

The general aim of this Newsletter is to promote cooperation and exchange of information and material among rice geneticists. Emphasis will be laid on standardization of gene symbols and presentation of current linkage maps, in addition to reporting new findings in the genetic study of rice.

Each issue will contain A) Special notices, B) Current linkage maps, C) List of genes and genetic stocks, D) List of recent publications, E) Research notes, and F) Mailing list. The Newsletter will be published annually.

The research notes should consist of short articles (abstracts with necessary tables and references). Each article should contain information that might otherwise not be available to interested workers, even if it does not merit formal publication. Particular strains used as experimental material should be briefly described. New findings on genes, linkage relations, and useful techniques can logically be reported here. Articles are published primarily for the benefit of members, and none of information may be used in publications by others without the consent of the respec- tive authors. Recent papers on rice genetics published in languages other than English can be summarized as a research note. Preliminary reports of research projects that might be published later as journal articles are also welcome.

Manuscripts should be sent to the Editor: Dr. H. I. Oka, National Institute of Genetics, Misima City, 411 Japan, or Dr. G. S. Khush, International Rice Research Institute, P.O. Box 933, Manila, Philippines.

For subscription, please write to the Secretary: Professor Y. Futsuhara, Faculty of Agriculture, Nagoya University, Chigusa-ku, Nagoya, 464 Japan.

The Symposium will be held at the International Rice Research Institute (IRRI, Los Banos, Philippines) in May 1985, and will be jointly sponsored by the IRRI and Japanese Rice Genetics Information Committee. The following topics will be discussed: 1) Systematics and evolution, 2) varietal differentiation and reproductive barriers, 3) rice karyotype, polyploids, aneuploids, and translocations, 4) genetic markers and linkage maps, 5) geographical distribution of genes, 6) genetics of physiological traits, 7) genetics of endosperm traits, 8) genetics of disease and insect resistance, 9) quantitative genetics, 10) cytoplasmic male sterility and restoration, 11) mutagenesis, 12) tissue and cell culture, 13) gene library for genetic engineering research, and 14) gene transfer techniques.

The proceedings will be published in a book form. An international committee for preparing the program has been established with the following membership: Co-chairmen: Drs. M. S. Swaminathan and M. Takahashi, Secretaries: Drs. G. S. Khush and H. I. Oka, Members: Drs. A. Abifarin (Liberia), T. T. Chang (IRRI), R. C. Chaudhary (India), M. H. Heu (Korea), M. Jacquot (France), Min Shao Kai (China), T. Kinoshita (Japan), M. Van Montagu (Belgium), J. N. Rutger (USA), B. H. Siwi (Indonesia), Ray Wu (USA), and S. M. H. Zaman (Bangladesh).

If you are interested in attending the Symposium, please write to one of the Secretaries at your earliest convenience. (G. S. Khush)

In 1963, the Committee on rice gene symbolization and linkage groups (chairman Dr. N. E. Jodon), appointed by the 6th (1955) Meeting of the Working Party on Rice Breeding, FAO International Rice Commission (IRC), proposed the general rules and standardized symbols for known genes. Since then, this report has served as a guide for rice geneticists. On account of new developments in rice genetics during the last two decades, however, the need for examination and revision of gene symbols and linkage groups has been progressively felt. Realizing this, the Japanese Rice Genetics Information Committee initiated the examination of the gene symbols and linkage groups. First, the Committee discussed the principles and accepted the following:

1) The symbols used should follow the above-mentioned international rules (given in Table 1) and the gene symbols thereby recommended (cf. Publ. List 1, 10, 19 & 32).

2) The symbols commonly used by many workers can be retained even if they do not fit the rules completely.

3) When a new gene is identified but its allelic relationships with previously reported mimic genes are not known, it is denoted by adding (t) to its symbol; (t means tentative). For examples, d-50(t).

4) Non-allelic loci (mimics, polymeric genes, etc.) are distinguished by a suffix letter or arabic numeral either on the same line after a hyphen or as a subscript.

5) When two or more different gene symbols have been used for the same gene, the one appearing in the earlier report is adopted so far as it satisfies the rules.

6) For revision of gene symbols used by an author, contact with the author to seek approval is necessary.

7) The list of genes includes those for which seed stocks are maintained. The gene symbols recommended by the Committee are shown in the List that follows.

Table 1.International rules adopted by ICG and the comments for application to rice genetics added by IRC

1. In naming hereditary factors, the use of languages of higher internationality should be given preference. (English is and probably will continue to be the language most commonly used by rice geneticists.)

2. Symbols of hereditary factors, derived from their original names, should be written in Roman letters of distinctive type, preferably in italics, and be as short as possible. (Symbols may be based on a key word or on an adjective-noun combination.)

3. Whenever unambiguous, the name and symbol of a dominant begin with a capital letter and those of a recessive with a small letter. (Non-controversial.)

4. Literal or numeral superscripts are used to represent the different members of an allelic series. (Same as 'convention' number 1 of Kadam and Ramiah [6].)

5. Standard or wild type alleles are designated by the gene symbols with + as a superscript or by + with the gene symbol as a superscript. In formulae the + alone may be used. (It hardly could be said that there is either a standard or a wild type in rice, and therefore the first part of this rule does not seem to apply. The + sign could be used in formulae if desired.)

6. Two or more genes having phenotypically similar effects are designated by a common basic symbol. Non-allelic loci (mimics, polymeric genes, etc.) are distinguished by an additional letter or Arabic numeral either on the same line after a hyphen or as a subscript. Alleles of independent mutational origin may be indicated by a superscript. (Here rice geneticists might follow 'convention' numbers 2 and 3 of Kadam and Ramiah [6] in using literal subscripts for complemen- tary genes and numeral subscripts for duplicate genes.)

7. Inhibitors, suppressors and enhancers are designated by the symbols I, Su, and En, or by i, su, and en if they are recessive, followed by a hyphen and the symbol of the allele affected. (This appears non-controversial.)

8. Whenever convenient, lethals should be designated by the letter l or L, and sterility and incompatability genes by s or S. (Would not be needed for albinos, which are always lethal.)

9. Linkage groups and corresponding chromosomes are preferably designated by Arabic numerals. ([In the past] Roman numerals have been used, but in the future this rule should be complied with.)

10. The letter X and Y are recommended to designate the sex chromosomes. (Does not apply.)

11. Genic formulae are written as fractions with the maternal alleles given first or above.

Each fraction corresponds to a single linkage group. Different linkage groups written in numerical sequence are separated by semicolons. Symbols of unlocated genes are placed within parentheses at the end of the formula. In euploids and aneuploids the gene symbols are repeated as many times as there are homologous loci. (Non-controversial.)

12. Chromosomal aberrations should be indicated by the abbreviations: Df for deficiency, Dp for duplication, In for inversion, T for translocation, Tp for transposition. (Cytologists and cytogeneticists will have use for these symbols in future work with rice.)

13. The zygotic number of chromosomes is indicated by 2n, the gametic number by n and the basic number by x. (Non-controversial usage.)

14. Symbols of extra-chromosomal factors should be enclosed within brackets and precede the genic formulae. (Non-controversial usage.)