By CHANG MAY CHOON

XAVIER Lim and Jae An arefive-year-old boys who see theworld through glasses – not formyopia but astigmatism.

They are among a growinggroup of pre-school children withproblems such as myopia or astig-matism, which is blurred visiondue to uneven curvature of theeyeball.

About 16 per cent of kindergar-ten children are short-sighted, ac-cording to the latest Health Pro-motion Board (HPB) figures from2011, up from 7 per cent in 2009.

There is no separate figure forastigmatism, which can occur to-gether with myopia, but the Singa-pore National Eye Centre (SNEC)said it is “quite common” among

kids are being detected at annualscreenings held by HPB at child-care centres and kindergartens.

About 25 per cent of the75,000 K1 and K2 childrenscreened each year are referredfor further assessment when theyfail the test, said HPB, which start-ed such screenings in 2002 to pre-vent and reduce the early onset ofmyopia. About 65 per cent of12-year-olds are myopic.

Jae’s mother, Mrs Lynn An, 34,said she noticed that he would rubhis eyes and see things up close.He was diagnosed with astigma-tism after failing the kindergarteneye test in June.

“I felt so sad for him that hehas to start wearing glasses so ear-ly in life, but I got over it quitequickly because I know he needs

images in the affected eye that itcannot adjust to seeing clearlyeven when given the best glasses.

“If it is not treated early, itmay lead to permanent poor vi-sion in the affected eye,” saidSNEC senior consultant ophthal-mologist Audrey Chia.

Dr Ngo cited a case of a boywho could not see clearly beyondhis outstretched fingers – he had500-degree astigmatism and700-degree myopia in his righteye. But his parents did not noticethis until he was screened in K1,as “he could still see with his goodeye”, said Dr Ngo.

Most children are born withsome degree of astigmatism. Butonly moderate-to-high levels ofover 150 degrees need correction,and this affects about 8 per centof the population. Astigmatism isbest treated before a child’s visualsystem is fully developed by ageseven or eight, say doctors.

Mrs An said Jae has one “lazy

but wears them only to kindergar-ten or when doing his homework.

“He keeps saying he can see,”said his mother, 37-year-old of-fice manager Rachel Soh. “Butwe’ve been encouraging him towear his glasses every day.”

Children can cope with visualproblems by tilting their head andsquinting to see better, said seniorconsultant optometrist Yap TiongPeng of optical chain Igard Group.

Mr Yap, who is studying howthe brainwaves of astigmatic chil-dren respond to wearing glasses,said the brain may take time to“start appreciating sharp vision”.

Some parents blame the use ofmobile devices for vision prob-lems. While this could be true formyopia, it is not so for astigma-tism, which usually stays stablethroughout life, say doctors. Butit can worsen due to droopy eyelidor cornea injury.

But some parents, like Mrs An,are not taking any chances.

By FENG ZENGKUN

SCIENTISTS in Singapore havemade a rare discovery in a com-mon local plant whose blue flow-ers are used for food colouring.

Researchers at Nanyang Tech-nological University (NTU) haveextracted a type of enzyme calleda ligase from the Clitoria ternatea,or the blue butterfly pea plant.

There are only four knownligases in the world, including thenew enzyme.

Ligases are important in the hu-man body as they “glue” aminoacids together to eventually formproteins, which are the buildingblocks for all cells in the body.

The scientists said their workcould lead to better understand-ing about how the human bodyforms cells, as well as how to re-pair mistakes that lead to diseasessuch as cancer.

They also found that the newenzyme – which they named bute-lase-1 after the plant’s Malay

name, bunga telang – glued aminoacids together about 10,000 timesfaster than the other three ligases,and did so without creating anyby-products.

Their research was publishedlast month in Nature ChemicalBiology, one of the prestigiousNature publishing group’s interna-tional scientific journals.

So far, other scientists havewritten four commentaries in vari-ous journals about the possibili-ties unlocked by the discovery.

Professor James Tam, the NTUteam’s lead scientist, said the en-zyme will be useful, for example,in creating peptide drugs for dis-ease treatment.

Peptides are short chains ofamino acids and drugs createdfrom them are safer than synthet-ic ones as they are found naturallyin the human body.

“But the peptide drugs are notvery stable. Their structure is likea string, and the stomach de-grades them by chopping them at

both ends,” said Prof Tam, who isalso director of NTU’s Drug Dis-covery Centre.

“But if we can glue the ends to-gether using the enzyme, then thedrugs may become more stable.”

The scientists found that thebutterfly pea plant itself uses theenzyme to form circular chains ofproteins, which enable the plantto survive extreme cold and heat.

The plant is commonly used asa herb to boost memory and as ananti-depressant. Its blue flowers

are also used for food colouringsuch as that found in pulut inti, aMalay glutinous rice dessert.

The NTU team’s research tookabout a year and is part of a largerprogramme led by Prof Tam thatanalyses active ingredients in foodand herbal medicine. The pro-gramme was awarded $10 millionby the National Research Founda-tion, and its goals include findingnew ways to ensure the safety ofplant-based products.

zengkun@sph.com.sg

Astigmatism ‘common’ inkids with vision problemsMore pre-schoolers being referred toeye clinics after annual screenings

NTU scientists find rare enzyme in common plant here

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