by the Laboratory of Freshwater Fish Stocks, Bioscience Center, Nagoya University, Nagoya 464-8601, Japan
See-through Medaka
Medaka mutants listed below are spontaneous mutants, most of which were collected by Tomita. This list is made by a modification of his paper (Tomita, 1992). The mutants and strains are welcome for use by researchers outside Nagoya University.
Among the mutants listed below, Si and Va are dominant to the wild type and Da is an incomplete dominant. The others are recessive. The r alleres and lf are sex-linked, and the others are autosomal.
| 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | |
| 1 | as | B' | b | bd | bdl | bp | bv | ci | cm | co |
| 2 | co-2 | cyc | Da | de | df-1 | df-2 | df-3 | df-4 | df-5 | df-6 |
| 3 | dg | di | dl | dl-2 | dm | dm-2 | d-rR | dx-1 | dx-2 | em |
| 4 | el | ey | fl | fl-2 | fl-3 | fl-4 | fm | fm-2 | fs | fu |
| 5 | fu-2 | fu-3 | fu-4 | fu-5 | fu-6 | fu-7 | gu | gu-3 | gu-4 | gu-5 |
| 6 | gu-7 | ha | ha-2 | i1 | i4 | i6 | ib (= i5) | i-3 | if | if-2 |
| 7 | il-1 | lf | lf-2 | ml-3 | mm | mo | pc | pl | r | rd |
| 8 | ro | rs | rs-2 | rs-3 | Si | sm | Va | vc | vl-1 | vl-2 |
| 9 | vl-3 | wl | wl-2 | wy |
as : fin ray segments are deleted occasionally.
B'* : : some melanophores are colorless.
b : all melanophores are colorless.
bd : melanophores are colorless at the larval stage and gradually change to black in adults.
bdl : melanophores are colorless at the larval stage and gradually change to light black in adults.
bp : melanin formation is delayed at the embryonic stage. Melanin in eyes is reduced in adults.
bv : black and light black melanophores in adults. (B >bv >bd >B' >bdl>b >bp)*
- ci :
the number of xanthophores is smaller than wild type.
- The number of well-developed leucophores is larger than wild type.
cm : melanin granules in melanophores are always concentrated.
co : pigment granules in xanthophores are always concentrated; linked with dx- 2.
co-2 : phenotype is similar to co but not linked with co .
cyc: cyclops
- Da:
double anal fins (dorsal fin resembles the anal fin). Caudal fin is rhombic.
- In heterozygotes with wild type, dorsal fin is large (the number of fin rays is larger than wild type).
de : the number of melanophores is lower than wild type in adults.
df-1 : fin membrane is deformed (fins folded) at the larval stage.
df-2 : phenotype is similar to df-1.
df-3 : phenotype is similar to df- 1.
df-4 : phenotype is similar to df- 1.
df-5 : phenotype is similar to df- 1.
df-6 : phenotype is similar to df- 1.
dg : deposition of guanine is less on the back of the body cavity.
di : pigment granules in xanthophores are always dispersed; linked with wl.
dl : melanophores are light black throughout life.
dl-2 : phenotype is similar to dl.
dm : pigment granules in melanophores and leucophores are always dispersed.
dm-2 : phenotype is similar to dm but not linked with dm.
d-rR : The body color is white in females (bb, XrXr) and orange-red in males (bb, XrYR). This strain was established by Tokio Yamamoto (1953).
dx-1 : xanthophores are weakly orange-red.
dx-2 : the same phenotype as dx-1 but not linked with dx-1.
- em : median fins (dorsal
and
anal fins) are enlarged posteriorly
- (the number of fin rays is larger than wild type).
el : eyeless
ey : eyes are deformed variously.
fl : the number of leucophores is lower than wild type at the larval stage.
fl-2 : phenotype is similar to fl.
fl-3 : phenotype is similar to fl.
fl-4 : phenotype is similar to fl.
fm : the number of melanophores is lower than wild type throughout life.
fm-2 : the number of melanophores is lower than wild type throughout life.
fs : dorsal and anal fins are small (interneural and interhemal spins are fused at the bases).
fu : vertebrae are fused to form a short body.
fu-2 : verbebrae are fused, short body.
fu-3 : phenotype is similar to fu-2.
fu-4 : phenotype is similar to fu- 2.
fu-5 : phenotype is similar to fu-2.
- fu-6 :
notochord is bent in a curved shape at the embryonic stage.
- Vertebrae are fused to form a short body in adults. Inbreeding is difficult. Maintenance is done by back-crosses (females often sterile).
fu-7 : phenotype is similar to fu-6. Inbreeding is easy.
gu : deposition of guanine in iridocytes is decreased throughout life.
gu-3 : deposition of guanine in eyes is decreased at the larval stage.
gu-4 : phenotype is similar to gu-3.
gu-5 : polymeric genes. Phenotype is similar to gu-3.
gu-7 : deposition of guanine in eyes is decreased at the larval stage, forming black-spotted eyes.
ha : auditory vesicles are swollen at the larval stage. Inner ears are deformed in adults. Swims in circles.
ha-2 : polymeric genes. Phenotypes are similar to ha.
i (i1) : A complete albino phenotype. Linked with ci. This mutant fish contains a 1.9-kb insertion of a transposable element Tol1 in the 1st exon of the tyrosinase gene (Koga et al., 1995).
ib (i5) : Melanin formation is delayed at the embryonic stage. One of the i-locus alleles containing a transposable element (unpublished data). (+>ib >i )
i-3 : albino. No linkage with i.
i4: A quasi-albino phenotype with pale orange-red skin and red-wine-colored eyes. One of the i-locus alleles containing the insertion of a transposable element, Tol-2, in the 5th exon of the tyrosinase gene (Koga et al. 1996).
i6: A complete albino phenotype. One of the i-locus alleles containing a 0.3 kb deletion including a part of the 3rd exon of the tyrosinase gene (Koga et al., 1999).
if : partial defect of fin rays.
if-2 : phenotype is similar to if.
il-1 : polymeric genes. Defect in guanine deposition in iridocytes except in body cavity and eyeballs throughout life.
lf : no visible leucophores throughout life.
lf-2 : leucophores are small in number and xanthophores are partially lacking (sometimes white/orange-red variegated).
ml-3 : the number of leucophores is larger than wild type at the larval stage.
mm : melanophores and leucophores are dendritic as in normal or non-dendritic.
mo : melanophores are light brown and no visible leucophores are in adults.
pc : polycysts in kidney.
pl : no pectoral fins throughout life.
r : xanthophores are colorless.
rd : xanthophores are weakly orange-red. (R >rd > r )*
ro : swims with rolling.
rs : scales are deformed.
rs-2 : small scales.
rs-3 : almost no scales, only a few large ones.
Si: a pair of iridocyte spots on brain membrane is absent.
sm : physiological color change of melanophores is slow.
- Va :
melanophores, leucophores and xanthophores are
sometimes absent.
- Homozygotes are lethal at the embryonic stage.
vc : melanophores and leucophores are sometimes absent. Lighter black than Va.
vl-1 : leucophores disappear 2 weeks after hatching and some leucophores reappear in adults.
vl-2 : leucophores disappear 2 weeks after hatching and a few leucophores reappear in adults.
vl-3 : phenotype is similar to vl-2.
wl : white leucophores at the larval stage.
wl-2 : phenotype is similar to wl.
wy : vertebral column bent wavily.
References
1. Aida, T. (1921)
On the inheritance of color in a freshwater fish,Aplocheilus latipes Temminck and Schlegel, with special reference to sex-linked inheritance. Genetics, 6, 554-573.
2. Tomita, H. (1992)
The lists of the mutants and strains of the medaka, common gambusia, silver crucian carp, goldfish, and golden venus fish maintained in the Laboratory of Freshwater Fish Stocks, Nagoya University. Fish Biol. J. Medaka 4, 45-47.
*Aida (1921, ref. 1 ) used the gene symbols, B, B', and R ( B > B' > b, R > r). B and R do not imply that they are the dominant mutants but represent the wild type, and therefore B > B' > b and R > r are equivalent to + > b' > b and + > r according to the current usage of gene symbols, respectively. The symbols B, B' and R are still being widely used in the field of medaka genetics, in memory of Aida's pioneering contribution to medaka genetics.