Also, Zebrafish

‘UK scientists who decoded a third of the human genome say their next target will be the zebrafish. They will use the genetic data from the colourful animal to help them decipher the functions of human genes. The work could shed light on common human birth defects and a host of other health problems, including those of the heart, blood and nervous system…The three-year project will be carried out at the Sanger Centre, just outside Cambridge, in an initiative that will again be funded by the Wellcome Trust medical research charity. The humble zebrafish, like the mouse and the fruit fly, has long been used as a model for human health in laboratory studies. Its genetic material, or genome, is about half the size of our own. The zebrafish has similar blood, kidney and optical systems to that of humans. .And Nobel prize-winning scientist Christiane Nusslein-Volhard from the Max-Planck Institute, Germany, added: "Zebrafish is the ideal organism to study the function of human genes." Once the genetic sequence of the zebrafish is known, scientists will be able to make changes to the animal's DNA to study how human inherited diseases might arise. Some mutations have already been identified in zebrafish that are similar to human blood disorders. International scientists announced this year, to great acclaim, that they had succeeded in completing the first, rough draft of the human genome. But much of the information gleaned from the "code of life" is meaningless unless there is something with which it can be compared. Hence there is a drive to read the genetic material of several other animals. The mouse genome, which is the focus of efforts by two rival groups of scientists, is close to completion. The entire fruit fly genome is already available on digital disk for reference. The dog and the chicken genomes are making slow progress…Some scientists are also calling for an international effort to decode the DNA of man's closest living relatives: the great apes.’ Helen Briggs, BBC

‘The zebrafish is now a well established model system. Its rise to prominence has been meteoric - only a decade ago, zebrafish research was small fry…Like other model organisms, the zebrafish research field had a founding father and a 'hometown'. Drosophila can look to Thomas Hunt Morgan and the 'flyroom' at Columbia University, and the nematode worm to Sydney Brenner and Cambridge; likewise the zebrafish pays homage to George Streisinger, a tropical fish enthusiast at the University of Oregon.’ Wellcome Trust, 2003

‘A comparative study of gene expression in hepatocellular carcinomas underscores the utility of zebrafish for human cancer research.’ Nature, 2006

‘The zebrafish (Danio rerio) has been long advocated as a model for cancer research, but little is known about the real molecular similarities between zebrafish and human tumors. Comparative analysis of microarray data from zebrafish liver tumors with those from four human tumor types revealed molecular conservation at various levels between fish and human tumors. This approach provides a useful strategy for identifying an expression signature that is strongly associated with a disease phenotype.’ Nature, 2006

"This builds on the seminal work, supported by the Wellcome Trust, on the human genome sequencing project and will help all our future studies on gene function, leading to health care benefits." Michael Dexter, Director, Wellcome Trust

Another organic laboratory; inches big -

how much further from gleaming white,

steel - torturing institutional strip-light,

of what has been Science’s modern domain -

back to the living blood-laboratory of Darwin,

coupled with new technologies to see beneath

all masquerades of flesh, egg, shape, form –

life will out, her patterns will not be shaken

off by any aeon, upstart species now lording

it over all; misusing, abusing advantage.

But Nature must humble all once more -

she has brought humans to their knees,

making them remember the fish, low worm

they were, and are under sophisticated skin -

close kin with this fish, chill black and white;

yet more holy exhibition of this genetic art,

binding craft - colours drain - photographs

developing of ourselves, once more at sea.

Blood brothers with the cold Zebrafish

Blood brothers with the cold Zebrafish,

yielding his similarities under stripes -

looking into water as we perceive air,

as nothing; silver impulses still flying

as our own sparkling, ancient currents,

transparent kidneys our own diagram.

His monochrome heart stayed in the sea,

already host, alchemising new creatures -

turning slowly into pumping red flower

under sun as he slowly metamorphosed;

his blood that was once clear sea, heating -

beating among warm blue, unfiltered light.

“Sounds as if being related to us might not come as quite as much of a shock to the Zebrafish, as there is already evidence of inter-species confusion.” Gillian K Ferguson

‘A technique that zebrafish researchers have embraced enthusiastically uses the gene for 'green fluorescent protein' to label specific cells in the embryo. As the protein is harmless and does indeed glow bright green (the gene having come from jellyfish originally), the fate of the cells can be followed as the embryo develops. "One of the most exciting things about fish is that you can study dynamic processes," says Professor Steve Wilson who studies zebrafish development at University College London. "The embryo is transparent, so you can watch things happen in the living embryo. I think this will allow the next generation of experiments to be undertaken. If you can watch what a cell is doing in the presence or absence of a gene product, you can say a lot more about what a gene is required for." Wellcome Trust, 2003

Green fluorescent protein gene

I munched some ‘green fluorescent protein gene’,

thinking it would give me that certain glow - shy,

I would shine in company, radiate good health,

cheer; (like those women who died of radiation

sickness having a laugh painting their teeth

with luminous yellow paint.during the War) -

my radiant complexion would be the envy

of all, like that rictus smile from injecting

poison into your face is all the rage - eat only

macro-biotic, inject Botulism in facial muscle;

harmless, of course. As night fell - only I

could read by my own light, jealous Moon

sick to her bone - my light was organic -

fuelled by food; my husband mistook me

for a ghost, visitation to the bedroom,

whereas I felt far more like an angel,

whose nature bleeds through imaginary

wing, halo concept, to allow us to see -

rank with artificial spirit, I glowed;

knowing soul-light is irreproducible.

‘The zebrafish has become an important model system in developmental biology and, more recently, in cancer research. The study by Lam et al. now establishes that carcinogen-induced liver tumors in zebra-fish recapitulate the molecular expression patterns of human liver cancers and possess features that correlate with progressively higher grades of malignancy. A "zebrafish liver tumor differentially expressed gene set" was identified by comparing gene expression profiles of zebrafish liver tumors with those of normal liver tissue and was then mapped to its human orthologs using Unigene clusters. Ontology annotation of the human orthologs of genes within the differentially expressed gene set revealed striking examples of the general molecular hallmarks of human cancer - including deregulation of the cell cycle, apoptosis, DNA replication and repair, and protein synthesis - as well as deregulation of liver-specific functions.’ Nature, 2006

The principle of creativity inherent in Nature

is stunning to the point we must say miracle;

preserving the same elaborate systems drawn

only from space, light, earth and water - her

chemistries, in creatures so diverse it’s farce;

blinding to evolution, cloaking her processes,

beings, lives, in fantastical patterns, workings -

as if we can see now the master plan, skeleton

preserved - not of bone, but light, imagination,

the force powering, gluing the same molecules;

Zebrafish livers and ours, flowering in tumours

indistinguishable; as expressed shadow - over-

excited genetic principle resulting in proliferation,

destruction - that once brought us both from water.

‘Scientists believe that studying the humble zebrafish may have helped solve the mystery of human skin colour. A team at Penn State University has found just one tiny change in a key gene plays a major role in determining skin pigmentation. The finding, published in Science, may help explain why people of European descent have lighter skin than those from Africa. It is hoped the research may lead to new ways to treat skin cancer. Potentially, it may also lead to the development of new ways to modify skin colour without damaging it by tanning or using harsh chemical lighteners. The genetic determination of human skin colour is one of biology's enduring mysteries. Alterations in some of these genes are associated with disorders such as albinism, which causes very light skin, but also vision problems. However, most of the genes responsible for normal differences in skin pigmentation have remained unknown. The gene identified by the Penn State team - called SLC24A5 - had not previously been suspected to be involved in pigmentation. Zebrafish are ideal for research because they share many similar genes with humans. They also have similar pigment cells, which, like humans, contain granules called melanosomes. The researchers found a variant of the zebrafish, called golden, had fewer, smaller and less heavily pigmented melanosomes than normal fish. They found the lighter pigmentation was caused by a mutation in the SLC24A5 gene which cuts production of a key protein. Adding protein from the normal zebrafish resulted in fish with a darker colouring. Next, the researchers analysed data from the human genome, and found a similar pattern. Most human populations carried the same version of the SLC24A5 gene, but people with a European ancestry carried a variant with just one mutation. This mutation appears, like the zebrafish, to result in fewer, smaller and lighter melanosomes. Further analysis showed that among people with mixed European and West African ancestry, those carrying the European form of the gene tended to have lighter skin. The findings suggest that this single gene controls up to 38% of the colour range in this mixed population. Researcher Dr Keith Cheng said the importance of the work extended beyond pigmentation. "We know so little about the genetic and evolutionary architecture of human traits. "We can not expect to use human genetics to understand complex diseases most effectively without first working out how fundamental characteristics, such as eye, hair, and skin colour, are determined. "Working out the details of pigmentation with help from model systems like zebrafish is a great paradigm for seeking understanding of other complex diseases." Dr Emma Knight, of Cancer Research UK, said: "The results of this research are intriguing but we shouldn't jump the gun and speculate about their implications for skin cancer. Much more research is needed to work out why Europeans have evolved a different version of SLC24A5 and what function this serves”.’ BBC, 2005

SLC24A5

Might we be sun-immune, after impairing sunlight,

mutating rays; happier in our skins, turning darker/

lighter, according to fashion, instead of pride in history,

home; colours evolution painted in us with such artistry,

sensitivity to environment. The golden fish has revealed

the source of her goldenness; rich alchemist gene turning

mutation into gold, solving enduring pigment mysteries -

except judgments stupid men make on the colour of skin.

Golden Fish

Golden fish, thus altered

by sun - centuries tuning