A Database for Triticeae and Avena
Newsletter (2010) 40:178-182
Rules for Nomenclature and Gene Symbolization in Barley
Jerome D. Franckowiak1 and Udda Lundqvist2
Station, Agti-Science Queensland,
Department of Employment, Economic Development and Innovation
Warwick, Queensland 4370, Australia
Genetic Resource Center
P.O. Box 41, SE-230 53 Alnarp,
In this volume of the Barley Genetics Newsletter the
recommended rules for nomenclature and gene symbolization in barley as reported
in BGN 2:11-14, BGN 11:1-16, BGN 21:11-14, BGN 26:4-8, BGN 31:76-79, BGN
34:132-136, BGN 35:114-149, BGN 37:100-104, BGN 38; 165-170 and BGN 39:77-81
are again reprinted. Also, the current lists of new and revised BGS
descriptions are presented by BGS number order (Table 2) and by locus symbol in
alphabetic order (Table 3) in this issue.
naming hereditary factors, the use of languages of higher internationality
should be given preference.
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
original name should be as descriptive as possible of the phenotype. All gene
symbols should consist of three letters.
new gene symbols should consist of three letters. Existing gene symbols of less
than three letters should be converted to the three-letter system whenever
symbols are revised. When appropriate, one or two letters should be added to
For example, add the letters "ap"
to "K" to produce the symbol "Kap"
to replace "K" as the symbol for Kapuze
(hooded). As another example, add the
letters "ud" to
"n" to produce the symbol "nud"
to replace "n" as the symbol for naked seed. Similarly the
letter "g" can be added to "ms" to produce
the symbol "msg" for genetic male
sterility and the letter "e" can be added to "ds" to produce the symbol "des"
for desynapsis. When inappropriate or when conflicts
arise, questions should be referred to the Committee on Genetic Marker Stocks,
Nomenclature, and Symbolization of the International Barley Genetics Symposium
unambiguous, the name and symbol of a dominant begin with a capital letter and
those of a recessive with a small letter.
AMENDMENT: When ambiguous (co-dominance,
incomplete dominance, etc.) all symbols should consist of a capital letter
followed by two small letters that designate the character, a number that
represents a particular locus, and a letter or letters that represents a
particular allele or mutational event at that particular locus.
COMMENTS: As an example, the
letters "Mdh" can be used to
designate the character malate dehydrogenase,
"Mdh1" would represent a particular locus for malate dehydrogenase and "Mdh1a",
"Mdh1b", "Mdh1c", etc. would represent
particular alleles or mutational events at the "Mdh1" locus.
Row number can be used as an example of symbolizing factors showing incomplete
dominance. At the present time, the symbol "v" is used to
represent the row number in Hordeum vulgare, "V"
is used to represent the row number in Hordeum distichum,
and "Vt" is used to
represent the row number in Hordeum deficiens.
According to the amendment to Rule 3, if row number were to be designated by
the letters "Vul", the designation
of the locus on chromosome 2 would then become "Vul1" and the
alleles "v", "V", and "Vt" would be designated "Vul1a",
"Vul1b", and "Vul1c".
SUPPLEMENTARY AMENDMENT: A period
should be placed before the allele symbol in the complete gene symbol.
COMMENTS: Since DNA sequences
similar to those of the original locus may occur at several positions in the Hordeum
vulgare genome, a three-letter symbol plus a number is inadequate to
represent all potential loci. Also, both numbers and letters have been assigned
to specific mutants and isozymes in Hordeum
vulgare. The six-rowed spike locus
is used as an example although the symbol Vul1 for row number in Hordeum
vulgare is not recommended because the botanical classification of Hordeum
spp has changed. The locus symbol vrs1 and the
name six-rowed spike 1 are recommended for the v locus. Gene symbols
recommended for common alleles at the vrs1 locus are vrs1.a, vrs1.b,
vrs1.c, and vrs1.t for the "v", "V",
"vlr", and "Vt" genes, respectively.
or numeral superscripts are used to represent the different members of an
AMENDMENT: All letters and
numbers used in symbolization should be written on one line; no superscripts or
subscripts should be used.
or wild type alleles are designated by the gene symbols with a + as a
superscript or by a + with the gene symbol as a superscript. In formulae, the +
alone may be used.
AMENDMENT: This rule will not be
used in barley symbolization.
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.
Barley gene symbols should consist of three letters that designate the
character, a number that represents a particular locus, and a letter or letters
that represents a particular allele or mutational
event at that particular locus. All letters and numbers should be written on
the same line without hyphens or spaces. Alleles or mutational events that have
not been assigned to a locus should be symbolized by three letters that
designate the character followed by two commas used to reserve space for the
locus number when determined, followed by a letter or letters representing the
particular allele or mutational event. After appropriate allele testing, the
correct locus number will be substituted for the commas. Where appropriate
(when assigning new symbols or when revising existing symbols) letters
representing alleles or mutational events should be assigned consecutively
without regard to locus number or priority in discovery or publication.
COMMENTS: The use of the proposed
system of symbolization can be illustrated by the desynaptic
mutants. Two loci are known: lc on chromosome
1 (7H) and ds on chromosome 3 (3H). These will
be resymbolized as des1a and des2b. A
large number of desynaptic mutants have been
collected. They will be designated des,,c,
etc. If allele tests show that des,,c
is at a different locus than des1 and des2, des,,c
will become des3c. If allele tests show that des,,d is at the same locus as des2, des,,d will become des2d. In practical use,
the symbol des will be used when speaking of desynapsis
in general or if only one locus was known for the character. The symbol des2
will be used when speaking of that particular locus,
and the symbol des2b will be used only when speaking of that
particular allele or mutational event. If additional designation is needed in
particular symbolization, it can be obtained by adding numbers behind the
allele letters, and, if still further designation is needed, letters can be
added to the symbol behind the last number. Symbolization consisting of
alternation of letters and numbers written on the same line without hyphens or
spaces will allow for the expansion of the symbol as future needs arise. In any
work with large numbers of polymeric gene mutants, every mutant has to be given
a designation not shared by any other mutant of this polymeric group and this
designation should become a part of the permanent symbol representing that
particular allele or mutational event. This requirement can be met by assigning
allele designations in consecutive order without regard to locus number.
SUPPLEMENTARY AMENDMENT: A period should be used instead of two commas
in gene symbols for mutants within a polymeric group that can
not be assigned to a specific locus.
COMMENTS: The des symbol
should be used when referring to desynapsis in
general; des1 and des2, for specific loci; des1.a and des2.b
for specific genes or alleles at their respective loci; and des.c, des.d, des.e etc., for desynaptic
mutants not assigned to a specific locus.
Even if the locus in question is the only one known
that affects a given phenotype, the three-letter basic symbol is followed by a
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
This rule is no longer appicable
and will not be used in barley symbolization.
convenient, lethals should be designated by the
letter l or L and sterility and incompatibility genes by s
COMMENTS: J.G. Moseman (BGN 2:145-147) proposed that the first of the
three letters for designating genes for reaction to pests should be R.
The second and third letters will be the genus and species names of the pest.
SUPPLEMENTARY COMMENT: A motion
was passed during the workshop on "Linkage Groups and Genetic Stock Collections"
at the Fifth International Barley Genetics Symposium in 1986 (Barley Genetics V:1056-1058, BGN 17:1-4), that the International Committee
for Nomenclature and Symbolization of Barley Genes should "recommend use
of Ml as the designation of genes for resistance to powdery mildew.”
9. Linkage groups and
corresponding chromosomes are preferably designated by Arabic numerals.
SUPPLEMENTARY AMENDMENT: The
current wheat homoeologous group numbering scheme
(the Triticeae system) is recommended for Hordeum
vulgare chromosomes. Arabic numerals followed by an H will indicate
specific barley chromosomes. The H. vulgare chromosomes should be 7H,
2H, 3H, 4H, 1H, 6H, and 5H instead of 1, 2, 3, 4, 5, 6, and 7, respectively.
letter X and Y are recommended to designate sex chromosomes.
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 parenthesis at the end of the formula. In euploids
and aneuploids, the gene symbols are repeated as many
times as there are homologous loci.
aberrations should be indicated by abbreviations: Df for deficiency, Dp
for duplication, In for inversion, T for translocation, Tp for transposition.
zygotic number of chromosomes is indicated by 2n, the gametic
number by n, and basic number by x.
of extra-chromosomal factors should be enclosed within brackets and precede the
recommendations made by the International Committee for Nomenclature and
Symbolization of Barley Genes at the Fourth International Barley Genetics
Symposium in 1981 (Barley Genetics IV:959-961) on gene and mutation
designations were as follows.
designations for genes and mutations. - Most of the present designations should
be maintained. However, new designations may be given, when additional
information indicates that new designations would aid in the identification of
genes and mutations.
designations for genes and mutations. - New genes or mutations will be designated
by characteristic, locus, allele, and then the order of identification or
mutational event. Three letters will be used to identify new characteristics.
Consecutive numbers will be used to identify the order of identification or
mutational event. Loci will be designated by numbers and alleles by letters
when they are identified. For example, des-6 indicates that this is the
sixth gene or mutation identified for the characteristic des (desynaptic). des 1-6 and des 2-7 indicate
that gene or mutational events 6 and 7 for the desynaptic
characteristic have been shown to be at different loci and those loci are then
designated 1 and 2, respectively. des 1a6 and des 1b8, indicate
that the gene or mutational events 6 and 8 for the characteristic desynaptic have been shown to be at different alleles at
locus 1 and those alleles are then designated a and b.
motion was passed during the workshop of the "Nomenclature and Gene
Symbolization Committee" at the Fifth International Barley Genetics
Symposium in 1986 (Barley Genetics V:1056-1058) that
"the recommended systems for
Nomenclature and Gene Symbolization of the International Committee be
published annually in the Barley Genetics Newsletter."
the workshop for ”Recommendations of Barley
Nomenclature” held at Saskatoon,
July 31, 1996 and adopted at the General Meeting of the Seventh International
Barley Genetics Symposium, it was recommended that a period instead of a dash
be used to designate the allele portion of the gene symbol. Consequently, the
first gene symbol for the characteristic des (desynapsis)
should be expressed as des1.a. The code des1 identifies a
specific locus. The period indicates that the symbol a
identifies a specific allele or mutational event that produces a desynaptic phenotype. (The allele symbol a will be
always associated with this specific desynaptic
mutant even if the locus symbol is changed based on subsequent research