Immortality

‘An unbroken chain of descent links the very first ur-gene with the genes active in your body now – an unbroken chain of perhaps fifty billion copyings over four billion years. There were no breaks or fatal mistakes along the way…if the genome is immortal, why does the body die? Four billion years of continuous photocopying has not dulled the message in your genes (partly because it is digital), yet the skin gradually loses its elasticity as we age…Because some cells cease doubling early and others continue, many tissues are created by more than fifty doublings, and because some tissues continue repairing themselves throughout life, certain cell lines may have doubled several hundred times during a long life. That means their chromosomes have been ‘photocopied’ several hundred times, enough to blur the message they contain. Yet fifty billion copyings since the dawn of life did not blur the genes you inherited. What is the difference? Part of the answer [is] a gene called TEP1. The product of TEP1 is a protein which forms part of a most unusual little biochemical machine called telemorase. Lack of telemorase causes, to put it bluntly, senescence. Addition of telemorase turns cells immortal…the biochemical machines that copy DNA, called polymerases, cannot start at the very tip of a DNA strand. They need to start several words into the text. Therefore the text gets a little shorter every time it is duplicated…At the end of the chromosome there occurs a releated stretch of meaningless ‘text’…This stretch of terminal tedium is known as a telomere. Its presence enables the DNA-copying devices to get started without cutting short any sense-containing ‘text’. Like an aglet, the little plastic bit on the end of a shoelace, it stops the end of the chromosome from fraying. But every time the chromosome is copied, a little bit of the telomere is left off…In your body, the telomeres are shortening at the rate of about thirty one ‘letters’ a year…that is why cells grow old and cease to thrive beyond a certain age.’ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000

Telomeres

From star, sea, and earth, we came –

four billion years of printing, copying;

matrix for holding us in existence

remaining - change and variation,

selection, decay - but always the same

few words repeated; skeleton of being,

hooks for organic life, insuring themselves

with telomeres, safety margins, expendable

borders - shelter of clever messages written

in code unbroken by any death – protective

gobbledy-gook; ingenious meaningless

letters, spun around gene-studded core -

essential information that must survive,

as life strives on through any darkness,

in the space an ant might be - human,

tiger, ostrich or whale - orchestrating

her ancient tools, dreams and chemicals,

to be - exist here, now, no other but this;

giving up some letters to the dark,

but willingly none that can speak.

Might this be the chemist’s high dream,

alchemist’s, magician’s? - Telomerase,

elixir of life, healing frayed telomeres,

the failing cells where death creeps up

erasing words – telomerase - cousin

of original inventor - RNA to DNA

transcription; relic and trophy

of the fruitful past. Relation

to the root of all organic life,

stored in our treasure houses;

host of that bright life force -

stunning will just to be alive.

‘Telemorase has been around since the dawn of life, it seems, and has used almost the same RNA template in all descendents…these telomerase genes are as close as we may get for finding the ‘genes for youth’. Telomerase seems to behave like the elixir of eternal life for cells.’ Matt Ridley, Genome: The Autobiography of a Species in 23 Chapters, Fourth Estate, 2000

The alchemist threw back his hood -

raised his shining hands up in the air,

shouting: “Hallelujah!” - like a man

who has seen a miracle - or Archimedes

in his bath: “Eureka!”; Watson, Crick -

as co-discoverers of the helical structure

of DNA: “We’ve discovered the secret

of life!”. In his white, shaking fingers -

a magic bottle; pure refined telomerase,

shimmering, swirling like a liquid script -

compatible with blood, silver as mercury,

moon-sheen, water-shiver; as interlocutor,

would he distribute the fluid as Jesus would,

to the sick, old, poor and hungry - or auction

his vial to the highest bidder - like a fabulous

painting blinded in a vault, never ever seen;

converted, perverted into cash – investment.

Stolen chemical of Nature’s ingenious soul,

would this formula of preservation keep alive

those least fit to represent humanity; products

of love freely created - gifted by the Universe.

*

Given enough years, seeds of immortality,

would we learn more and yet more of love;

as passion has burned brilliant red messages

upon my heart, printed my perfecting spirit -

though my child has taught the true lesson,

meaning of love, in eternity’s split second.

BITTER TASTE

‘Researchers have taken a big leap forward in understanding our sense of taste by identifying the genes that enable us to recognise bitter substances. This discovery could eventually lead to medicines which mask their own bitter taste, an important goal given that studies have shown that patients often avoid taking vital drugs if they taste foul. The research might even result in agricultural sprays which the target the taste buds of pests to prevent them from eating crops. Cells in our tongues sense four basic tastes - sweet, salty, sour and bitter - plus a fifth, monosodium glutamate. But until now scientists did not know exactly how we tasted bitter and sweet things. Several different research groups have been mining genomic data and contributing to the discovery of bitter taste receptors. Scientists at Harvard Medical School used information from the Human Genome Project (HGP)…"The HGP is a fantastic resource," said neurobiologist Dr Linda Buck, one of the research team. "We couldn't have done the work without it." The Harvard team began by looking through a database of mouse genes. They zoomed in on the part of a chromosome where genetic mutations had been shown to knock out a rodent's sense for bitter food. They then used the HGP's powerful database technology to call up the corresponding location in human DNA. Trawling though it, they found a whole cluster of genes coding for cell receptors. These are proteins that poke out of the cell wall and signal the presence of a particular taste molecule. They do this by having a complementary shape to the taste molecule, rather like a lock and key. To prove that the receptor genes they had found did in fact produce the taste receptors, the scientists analysed the cells in mouse taste buds. They found that the genes did indeed produce receptor proteins and furthermore the genes were not active in any other cells in the body. "These findings are important in explaining why we perceive so many tastes as bitter," said Dr Buck. "It's because there are so many types of receptors for this one taste. Some of these may turn out to be sweet receptors, but my money is on most of them being for bitter tastes." Dr Buck plans to use the information to find out what happens in our brains when we taste bitter foods. But pharmaceutical companies may well be interested in developing additives to medicines that lock up bitter-taste receptors. This would stop us from perceiving the terrible taste of many medicines. Chemical companies may also benefit from research into insects' sense of taste as a safer and more environmentally friendly alternative to pesticides. The research is published in the journal Nature in which Dr Stuart Firestein of Columbia University comments: “…with the receptors that we now have and the application of a similar strategy to newly available genome data, it should be well within our power to lick these problems”.’ BBC Science, 2000

Bitter Taste

Our sensual tongues, gene-clustered,

screen for the vital tastes of things –

how like humans to develop more genes

for detection of bitter tastes than sweet -

though most poisons do twist our lips - 

another way the Genome keeps us safe;

unless overrode by the lovesick heart,

like poor Romeo. Nature painting her

spiders, frogs and wasps with warning stripes;

like you should have - like rugby-jumper skin.

I did not taste you bitter on my tongue, only

the condensed, sweetened words you spoke;

the milk of kindness, spoonfuls of sugar -

verbal chocolate, mouth-honey - physical

golden syrup on the lips, which helped

your deception go down – delightfully.

As locusts might be fooled, munching

beetles, from golden crops and wood -

maybe our junk food; killer plague,

brightly packaged like pink-coated,

slow arsenic - the force-fed, stealth

transfats, additives - bad chemicals

they poison our children with, could be

stripped to taste as their genetic truths -

as chemicals disuised beneath food-skin.

Maybe then, our tongues could recover -

we will remember rare honey, fruit’s

unadulterated succulence, pure sugar;

sweet green taste of leaves, full of rain,

nutritious earth, light converted to food.

HEART MUSCLE GENE

‘The physician-scientists who are studying heart disease will know as far as it's possible to know the fine differences between the various clinical pathologies. Some are reaching into the raw [sequence] data to make those distinctions already.’ Richard Gibbs, Director, Genome Sequencing Center, Baylor College of Medicine, Houston, US

‘A family of Israeli Bedouins may have helped scientists identify a gene responsible for a rare - and often fatal - heart defect. Polymorphic ventricular tachycardia (PVT) involves a fast and irregular heartbeat and seizures, and primarily affects young children. Now scientists at the Weizmann Institute of Science, and the Sheba Medical Center in Israel believe that they have found a gene - CASQ2 - which plays a role. Their research, published in the American Journal of Human Genetics, could help doctors find treatments for these "at risk" children. The first clues came when an eight-year-old girl - a member of a Bedouin tribe living in northern Israel - fainted after exercise, and was taken to hospital. Questioning revealed that her two younger brothers suffered from the same symptoms, and two other siblings had already died from the disease.  Professor Michael Eldar, chief of the heart institute at Sheba Medical Center, learned that several other families in the girl's village had a similar medical history. The families are thought to be the descendents of three brothers who settled in northern Israel 200 years ago. All these facts alerted researchers to the possibility that a gene for the condition could be identified in the village. In seven families alone, 13 children with PVT were found and treated - nine children had already died from the condition. Eventually the Human Genome Project threw up a potential candidate gene because it plays an important role in the working of heart muscle cells. It turned out that the children with the defect had a mutation in the gene. This is the second gene to be discovered which has a relevance to PVT. Doctors have already found a mutation in another gene, RYR2, which causes a form of the disease. Both genes appear to be different parts of the same chemical process which helps the body control the heart muscle. The genes should help doctors screen families for children who are at risk of the disease, and perhaps design better-targeted drugs to help correct the problem.’ BBC, 2002

Sprung Muscle

The sprung muscle, marking our personal time;

organic clock, internal drum, dark chest plum -

pictures of Christ show how it charges - radiates,

through skin, biological limits; writing metaphors

in other hearts with red sea-ink; pumping bass notes

for other physical harmonies keeping time - genetic

tunes played on the body instrument - physical fire

and oil to power this whole contraption, trembling

on Earth a while; out of all possibility, living, heated.

How metaphors have taken root in the body’s earth -

flower in the symmetrical red heart, symbolic satin,

emblazoning itself upon life, like the cross for love.

Gene of Delight

There is a flashing gene of delight -

seen activating my little boy’s face,

when a twinkling Red Admiral butterfly

unexpectedly decorates his little finger -

sunning herself - mistaking

his pinky for a comfy twig;

and his child smell