Genetics of eye colour unlocked

Scientists have made a breakthrough in their understanding of the genetics behind human eye colour.
They found that just a few "letters" out of the six billion that make up the genetic code are responsible for most of the variation in human eye colour.



The research, by a team of scientists from Queensland, Australia, will appear in a forthcoming issue of the American Journal of Human Genetics.



The findings are based on a genetic study of nearly 4,000 individuals.
One of the changes is like switching the light on and off, while the other is like changing the light bulb from brown to green Richard Sturm, University of QueenslandDifferences in eye colour are largely down to "single nucleotide polymorphisms" (SNPs - pronounced "snips"); variations in the sequence of letters that make up a single strand of human DNA.


SNPs represent a change of just one letter in the genetic sequence. These changes, or mutations, in our DNA can have important consequences for how the gene gets physically expressed.
All the SNPs are located near a gene called OCA2. This gene produces a protein that helps give hair, skin and eyes their colour. And mutations in OCA2 cause the most common type of albinism.

Brown and blue

The study, which focused on twins, their siblings and parents, shows - conclusively - that there is no "gene" for eye colour.
THE DNA MOLECULE




The double-stranded DNA molecule is held together by chemical components called bases
Adenine (A) bonds with thymine (T); cytosine(C) bonds with guanine (G)
Groupings of these "letters" form "code of life"; there are about 2.9 billion base-pairs in the human genome wound into 24 distinct bundles, or chromosomes


Written in the DNA are about 20-25,000 genes which human cells use as starting templates to make proteins; these sophisticated molecules build and maintain our bodiesEveryone has two copies of a SNP. So there are several possible combinations, some of which are more heavily associated with, for example, blue eyes, than with brown eyes.



In short, these combinations strongly influence the colour of a person's eyes, but they are not the final word.
Dr Richard Sturm and his colleagues found three SNPs near the start of the OCA2 gene that were linked to blue eye colour.



"The SNPs we've identified in themselves are not functionally causing the eye colour change, but they are linked very, very closely to something that is," Dr Sturm, from the University of Queensland, told BBC News.
"When OCA2 is knocked out, there is a loss of pigmentation. The position of these SNPs right at the start of the gene means it is possible we're looking at a change in the regulation of the gene in people with blue eye colour."
Functional change



So these SNPs, at the start of OCA2, probably regulate how much of the pigmentation protein is produced by the gene. People with brown eyes might have a lot of this protein, while people with blue eyes have less.
However, the single letter changes involved in green eyes may actually produce functional changes in the pigmentation protein.



The researchers found SNPs at another position in the OCA2 region - linked to green eyes - that resulted in changes to amino acids (the building blocks of a protein).
"To use an analogy, one of the changes is like switching the light on and off, while the other is like changing the light bulb from brown to green," said Dr Sturm.



Altogether, the single letter changes identified in the study accounted for 74% of total variation in eye colour, the researchers said. The study was a collaboration between researchers at the Queensland Institute of Medical Research and the University of Queensland, both in Brisbane.
source bbc

iPhone surprises technology world

A net phone called the iPhone has been launched by Linksys just weeks before analysts were expecting Apple to release a similarly-named device.

The wireless iPhone allows users to make free or low-cost internet phone calls using the Skype service.
It joins a growing market of phones which use wi-fi to make telephone calls instead of traditional mobile networks.

There has been intense speculation about Apple entering the mobile market for the last few months. Wireless net telephones are growing in popularity because they offer a low-cost alternative to making mobile phone calls.

The phones can connect to wi-fi networks - which are often free or low-cost to access - and access the net to make telephone calls, using Voice over Internet Protocol (Voip).
Analysts predict Increasingly, mobile phone manufacturers and operators are incorporating Voip services into handsets.

Apple has neither confirmed nor denied that it is working on a mobile phone but speculation has continued for months with many analysts predicting it will be unveiled in January in San Francisco.

Jupiter Research analyst Michael Gartenberg said the speculation around the Apple product - which was expected to be called iPhone - showed there was "pent up demand for something from Apple".

Many analysts predict that Apple will launch a device which combines the features of a mobile phone with its popular iPod. But there is uncertainty over whether the device will simply be a Voip handset or will also connect to mobile networks.

Jupiter analyst Thomas Husson, told the BBC News website, that he did not expect any Apple phone, if one were launched, to have an immediate impact on the mobile market.
'Disruptive'
"It's a very competitive market. It will take time for Apple to be disruptive."
He said that any Apple phone would most likely be sold direct to consumers, rather than through a mobile operator.

That would mean customers would have to pay a premium for the phone, as it would not then be subsidised. "Apple would need to offer a compelling phone experience," he said.
The Linksys iPhone comes in two models - a $180 (£92) model which can make Skype phone calls and a $200 (£102) model which is a dual Skype and landline phone.

President Declares 2007 Year Of Action

President J.A. Kufuor has declared that 2007 will be a year of action.He, therefore, asked Ghanaians to change their attitudes and rise up to meet the challenges and the programmes lined up for the year.

The President was responding to remarks made by the Chairman of the Council of State, Professor Daniel Adzei-Bekoe, at the last quarterly meeting between him and the Council of State at the Castle, Osu, yesterday.

After the opening remarks by the President and Professor Adzei-Bekoe, the meeting retired into a closed-door session.The President said 2007 would begin with Ghana playing host to the President of Germany, other African leaders and representatives of youth groups from all over the world at a forum intended to discuss the vision and arrangements for the emerging global village.

The forum, he said, would be followed almost immediately with a lecture by the outgoing United Nations Secretary General, Mr Kofi Annan, to kick-start the country’s Golden Jubilee celebrations.

He said Mr Annan, who had had a distinguished diplomatic career and also brought honour to the country, needed to be given a hero’s welcome to Ghana when he retired home next year.Besides the celebration of the country’s Golden Jubilee, the country would also be the venue for the African Union Summit and Conference on the Africa Growth and Opportunities Act (AGOA) to be attended by all beneficiary countries of the facility to map out strategies to maximise benefits under the facility.

The year 2007, he said, would be the period for the country to complete its preparations towards hosting the African Cup of Nations (CAN) in 2008.Again, he said, the year would witness the earnest implementation of the programme drawn up to utilise the $547 million facility given to the country under the Millennium Challenge Account (MCA) of the US.

The President said all those events, as well as other engagements, had been lined up at a time when the sanitation situation was not the best, while crimes such as cocaine trafficking posed a threat to the international image of the country.

He said such challenges could be best overcome with the active participation of all Ghanaians and, therefore, called for co-operation from all citizens to contribute their quota towards dealing with those difficulties for a successful year.As part of efforts to deal with the cocaine menace, the President said, the security agencies had busted another group of people suspected to be dealing in cocaine.

Reports submitted to his office, he said, indicated that some officials of a reputable company on the Spintex Road in Accra noted for rice importation had been busted for allegedly dealing in cocaine.Earlier, Professor Adzei-Bekoe commended the President for the progress that the country had made in the year 2006.

“We have maintained our economic stability, in spite of the frightening hike in oil prices and the impact that this has had on the cost of transportation and electric power for industrial and for domestic use,” he stated.“Fortunately, prices have come down significantly and the trend continues, though the downward trend has not been as dramatic as the increases months ago,” he added.

Professor Adzei-Bekoe said by the participation of the President in various forums and negotiations which had gone on with the host countries, he had secured for Ghana positive indications of support which could bring much needed relief in the short and medium terms.

He, however, expressed concern about some issues, including Dagbon and cocaine trafficking, and appealed to the parties involved in the Dagbon case to follow the road map which they had already signed for peace to prevail.
Source:Graphic

Police Probe Burning Of Currencies By A Chinese

The police are investigating a case in which a Chinese working in Ghana, Liu Jianpu, allegedly burnt a Ghanaian currency note, together with the Chinese yuan and the US dollar, for ritual purposes at Asokwa in Kumasi.

Jianpu, who works with the China Henan Guo Construction Company, which is drilling boreholes in the country, claimed that what he burnt were photocopies and not the original notes.

The police have consequently granted him bail while investigations continue. The Ashanti Regional Police Commander, Assistant Commissioner of Police (ACP) Frank Adu-Poku, told the Daily Graphic that at the moment the exhibits in the custody of the police were photocopies of a ¢20,000 note, a 100 Chinese yuan note and a $100 note.

He said on December 19, this year, three residents of Dadiesoaba, a suburb of Kumasi, reported to the police that they had seen some Chinese burning the currency notes at Asokwa.Policemen were, therefore, dispatched to the scene and they saw the ashes of burnt photocopies of a ¢20,000 note, a 100 yuan note, and $100.

When Jianpu, who was said to be the man at the centre of the act, was questioned, he explained that they had been performing some rituals to mark one week of the death of their colleague, Du Jia Quan, and to bid him farewell in line with Chinese custom and tradition.

ACP Adu-Poku stated that Jianpu further explained that what they had used were photocopies of the currency notes, as well as some favourite fruits of the deceased when he was alive.
Source:Graphic