Dark Locus: Gold Phenotypes
The allele for gold is on the dark locus and is designated with the
symbol g.
The only allele at this locus that appears in gold phenotypes is:
Gold (g)






Gold is a recessive trait that only expresses when the angelfish is
homozygous for gold (g/g). Gold is recessive to the wild type and to
the other non-wild alleles at this locus: dark (D), marble (M), and
gold marble (Gm). As shown in the table below, gold will not express
when paired with any allele at the dark locus other than gold.
Interaction between Gold and Other Alleles at
the Dark Locus |
Alleles |
+ |
D |
M |
Gm |
g |
g |
+/g
silver |
D/g
Hybrid black |
M/g
Marble |
Gm/g
Gold Marble |
g/g
Gold |
A gold angelfish is generally a light golden color, with a darker
yellow or orange color on the crown.
Factors that Affect Expression of the Gold Phenotype
Gold is constant in its expression. Environmental conditions do not
change the phenotype. Gold angelfish raised under a variety of
environmental conditions including different lengths of daily light
will always show the gold phenotype.
Changes in the Phenotype as the Angelfish Matures
The gold coloration is evident in very tiny fry. As a gold angelfish
matures, the color will deepen and the crown will take on a dark
yellow to orange color at maturity.
Gene Interactions
When gold is present heterozygously (single dose of gold) it does not
modify the expression of any alleles at other loci. However when gold
is present in homozygous form (g/g), it is epistatic to (suppresses
the expression of) some alleles at other loci. It is reported to
suppress the expression of smokey and the expression of halfblack. It
may also suppress the expression of zebra, but information was not
found to confirm the interaction between zebra and gold.
Gold ghost (g/g – S/+) is shown as a separate phenotype in the table,
but the difference is subtle. Gold ghost can be distinguished in fry
during the first few weeks of growth. Once angelfish fry are large
enough to distinguish some features in coloration and marking, at
about two weeks free swimming, until they are 6-7 weeks free swimming,
a gold will have faint body stripes, whereas the gold ghost will be
lacking the body stripes. After that, the stripes can no longer be
seen on the gold. Gold and gold ghost genotypes have similar
phenotypic expression, however gold ghosts will tend to be a little
paler in coloration than non-ghosts.
Addition of two doses of pearlscale to a gold results in a beautiful
angelfish in which the entire body is highly reflective of light, and
appears very shiny.
Phenotypes with Gold (g/g) and Alleles at
other Loci |
Alleles |
g/g |
Z/+, Z/Z |
[1] |
S/+ |
Gold Ghost |
S/S |
Gold Blushing (Sunset) |
Sm/+, Sm/Sm |
Gold |
h/h |
Gold |
a/a |
Albino Gold |
p/p |
Gold Pearlscale
 |
V/+ |
Gold Veil Tail |
V/V |
Gold Super Veil Tail |
Table
note: [1] Information was not found to confirm the interaction between
gold and zebra.
Links
to more information about black phenotypes
Dr. Joanne Norton, FAMA: July 1984; Vol. 7, #7
Dr. Joanne Norton, FAMA: September 1988, Vol. 11, #9
Dr. Joanne Norton, FAMA: May 1990, Vol. 13, #5
Dr. Joanne Norton, FAMA: December 1993, Vol. 16, #12
Approved by The Angelfish
Society Standards Committee on February 11, 2007.