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The Affymetrix Apex 3 expedition to Bolivia was successfully completed in June 2011. Below is a record of some of the diary entries, videos and photos taken during the trip.

Video Diary 4 "Pre-Descent"

0900h Thursday 23/06/2011, Michael Thompson

Video Diary 3 "Halfway There"

1200h Sunday 19/06/2011, Michael Thompson 

Expedition blog

1st Day James' account

1200h Thursday 16/06/2011

The group awoke on the early side of 6AM to meet the minivan and two pick-ups waiting to take us on our way. The heady excitement in the air easily cut through the biting cold of the La Paz winter morning. After heaping one week's essentials into any spare nook in our transport convoy, we set off through still-dark streets to Chacaltaya. Sandy and I were in a pick-up that soon split off from the main group; we had been given the job of picking up the local cook who had agreed to come up to the lab with us. We were aware of the gravity of the task-in-hand: three square meals of Bolivian culinary flair would surely be the best remedy for the trials of the 5200m Chacaltaya altitude.


Finding her shivering at the agreed rendezvous point, weighed down with bags of supplies for the hungry campers, we sped off to join the others.

As we left the thin spread of La Paz behind, the city roads faded into a roughly hewn path dissecting an arid landscape of bleached grassland. This seemed to be the only life comfortable in the competing hostilities of the piercing UV and the ghostly thin air. Our pick-up, a beastly Toyota Hilux, growled as it wound its way up the winding path that formed our 1500m ascent. The sun began to rise over the hillside, revealing eerily beautiful pools of water sleeping in crevices drawn into the rock. Climbing a little further, these gave way to islets of ice that seemed to pave the way to the snowy peak of Huayna Potosi.

Our confusion as to how the 14-seater minivan could have navigated the pendulum of hairpin bends was resolved as we passed it with 15 minutes remaining to the top. The driver had given up, resigned to letting the more mobile pick-ups grind up the final sprint. Distracted by the barren panorama around us, we didn't catch sight of the laboratory until it suddenly loomed out in front of us. It was bigger than expected, an expansive patchwork of browns and greys that created the impression of a thoroughly worn-in Alpine ski lodge.

A few members of the group had driven up the night before to scout out the accommodation. In contrast to the fresh faces we had last seen in La Paz 16 hours previously, what now greeted us was a host of gaunt apathetic figures, incapable of being swept up in the enthusiasm of the main group's arrival. The first night had ground them down with incredible speed. These Chacaltaya veterans warned us that it would take 3 or 4 hours for the first explosive symptoms to take hold; a ticking time bomb that gifted you with an initial feeling of immunity.

The first day for most of us was an alternating series of highs and lows. The textbooks were right: several members of the group were struck near-instantly with what the standard questionnaires would call incapacitating headaches and severe nausea. Almost as troubling as the full-throated effects themselves was the knowledge that your body could take a turn for the worse at a moment's notice. Caroline, our expedition doctor on the scene, has been a hugely helpful figure for those who need it.

Participation in the study requires that we stay at this altitude for the full 8 days, but everyone knows that there are two jeeps with a pair of very patient drivers waiting outside should any volunteer need to escape down to the comparatively oxygen-rich environment of La Paz.

Once most of us had gained the upper hand on the conditions, some set about the serious business of setting up tournaments of table football, while others played cards or vegetated with books. This would be a sloth-like start to the expedition, though fortunately one punctuated by meaty Bolivian feasts masterminded by our resident chefs. During our first night here, we were reminded that this was anything but a luxury break away; while most of us attempted to get some broken rest in our sleeping bags, the weather outside plummeted well into the minus digits.


Chacaltaya's plumbing supplying the toilet facilities put up a strong fight but eventually gave in to the frost. This meant bad news for those tormented few with stomach bugs picked up at La Paz's cheap but delicious street stalls. By morning, the lavatory area was a no man's zone. Thankfully Mark Williams, scientist and handyman, was at hand at 4AM to dig an improvised cess pit outside the lab, using only a fragment of slate and his bare hands. Having endured this minor setback, we are currently bracing ourselves, ready for what the next 7 days may have in store.

James Barclay

Video Diary 2

1600h Wednesday 15/06/2011

Another busy day in La Paz 

Posted by Ally Rocke on Tuesday 3st June, 2014


14:35h Wednesday 15/06/11

Chris Pennington

After three days in La Paz, we have learnt about how things are done in Bolivia. Road blocks and finding dry ice do not go well together, but everything is sorted now. The advanced party of 4 interpid men will go up to the lab today.

The experiments went well yesterday with some interesting results. The rest of the group will ascend tomorrow. One of the volunteers has done a video diary and we hope to upload some videos soon.


0800h Sunday 12/06/11

Andrew Beck, expedition leader

After all the fun of three international airports we have finally arrived safely at the hostel. We are all sat around breakfast looking forward to the rest of the trip; moral is high... at the moment!


Scientific Background

Even in people who feel completely well at high altitude, there is an unexplained leakage of fluid out of the blood vessels. We know that this is caused by a shortage of oxygen, but we have very little understanding of the process. In fact, the same thing happens to severely ill patients in intensive care units. If we knew how to prevent fluid leakage, we could save lives both in the mountains and back home at sea level.


We have three test days in the lab.

Using state-of-the-art technology generously provided by our main sponsor, Affymetrix, we will examine in unprecedented detail the response of circulating white blood cells to altitude exposure.

We will use a portable ultrasound machine (kindly supplied by Toshiba) to measure fluid leakage as accurately as possible in the lungs, heart and other tissues.

We will also take a small amount of blood from each research volunteer on each of the test days to look for hormones and chemicals that may be causing fluid leakage.

We also aim to assess the blood vessels in the eye, and how, if at all, visual acuity and colour perception is affected by altitude.

We will also be completing a number of psychological questionnaires and experiments to see how volunteers cope with altitude.


All protocols have been ethically approved by the Lothian Regional Ethics Committee. If you have any questions about our research protocols, please Email us.

The research



November 2010: Prospective volunteers may fill in an application form

December 2010: Prospective volunteers are interviewed

January 2011: The organising committee finalise the volunteer crew

January - May 2011: Volunteers are expected to actively fundraise and contribute to the research. Volunteers will be preparing for their time in Bolivia.

May 2011: All those going on the expedition will complete a sea-level test day at the Wellcome Trust facility at the Western General Hospital.



11th-15th June 2011: La-Paz

Volunteers will have an orientation period in Bolivia's capital city (3500m). During this time, we will undertake further measurements and tests, and take in the sights of the city.

15th-22nd June 2011: Chacaltaya Laboratory

Volunteers will ascend to Chacaltaya laboratory (5200m) on the 18th June by Land Rover. On day 1, 3 and 5 in the lab we will undertake more tests. On other days, volunteers are free to walk in the surrounding area in groups.



22nd June-1st July 2011: Free time

Volunteers will descend from Chacaltaya to La Paz, and then have the remainder of the time at their leisure.

Some volunteers are planning on climbing Sajama, the highest mountain in Bolivia, at 6,500m. Others are planning on heading to Lake Titicaca to the east, or the Salaar de Uyuni salt flats to the south.

Volunteers are free to fly back to the UK when they wish, or continue their travels elsewhere.



The organising committee and any interested volunteers are planning to continue the APEX ethos and bring our work to the wider community in the form of lectures, articles and discussions to the research and student bodies of Edinburgh and surrounds.

In addition, a number of the committee will be using the samples and data samples to write a scientific paper for a high-impact journal.

by Chris Pennington



APEX 3 is delighted to be endorsed by leading figures in both mountaineering and altitude medicine circles.


Sir Chris Bonington is one of Britain's most accomplished mountaineers.

"These young men deserve every encouragement. They have my full support."


Youngest Briton to the South Pole and previous visitor to Chacaltaya.

"Your expedition sounds like it it will make a brilliant contribution to science, far more than our brief visit to the mountain."

Organising Committee

The organising committee consists of seven University of Edinburgh medical students, and began organising the Affymetrix Apex 3 expedition in October 2009.


  • Expedition Leader: Andrew Beck

  • James Barclay

  • Hannah Dunton

  • Rachel Ellis

  • Stuart Gallacher

  • Chris Pennington

  • Mark Williams

Expedition Doctor

The expedition doctor is an experienced expert in expedition medicine.

  • Expedition Doctor: Dr. Caroline Heggie



The expedition was advertised around the University of Edinburgh campus and through the student press. Thusly, volunteers were drawn mainly from the University of Edinburgh, although we had interest from numerous Universities and Institutions, as well as the general public.

  • Kim Ah-See

  • Hannah Armstrong

  • Alex Bain

  • Claire Cassidy-Kojima

  • Rachel Crockett

  • Andrew Hunter

  • Rebecca Jackson

  • Sandy Jackson

  • Phil Jennings

  • Charlie Jones

  • Roman Kapetanevich

  • Becci Lewis

  • Josh McIntyre

  • Jill Macfarlane

  • Shona Main

  • Michael Thompson

  • Duncan Rutherford

  • Ali Rocke

  • Katie Smith

  • Jamie Stewart

  • Scott Veitch

  • Lizzie Wastnedge


Ultrasonographer: Shane O'Hanlon


Research Community

We have been working closely with a number of laboratories in Edinburgh in the lead-up to the expedition, and will continue to use the knowledge and facilities of these generous groups and individuals who have helped us so far.


Affymetrix Apex 3 is run by seven University of Edinburgh medical students who are travelling with 21 volunteers, an expedition doctor and an ultrasonographer to high altitude in June 2011.


Affymetrix Apex 3 crucially relies on the sponsorship from a wide array of supporters. We have kindly received sponsorship from the following companies and individuals:


We have also kindly recieved grants from the following bodies:

  • Stirlingshire Educational Trust

  • Rotary Club of Edinburgh

We thank all of our sponsors for their continued support for our expedition. All sponsors will receive significant exposure in the media, particularly to the research and student bodies of the University of Edinburgh. In addition, we will provide a comprehensive expedition report to all sponsors on our return.

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