The article mentioned unknown repercussion to biodiversity and ecology of the environment. For example a bat can consume thousands of mosquitoes in a single night (http://www.sandiegozoo.org/animalbytes/t-bat.html
As a geneticist and a naturalist, I have seen the many evils of GMO running rampant in the US, foremost Monsanto
's self destructive seeds. I can't eat rice, corn, and many soy as they have all been contaminated genetically. White rice are harder to digest as they are altered significantly ... and many cross breed with wild strains. Many rice species just sit in my stomach... and feel heavy like ... wood and glue.... way to go goddamn dumb ass juvenile GMO science.
To answer the OP, these GMO mosquitoes have some of the genes and gene pathways altered so these genes don't get expressed into necessary hormone and proteins to further growth. Specifically.... "The lethal gene RIDL produces a protein called tTA, which is able to act as a switch to control the activity of other genes. In the modified insects, the presence of high levels of this gene causes the machinery in the insect’s cells to go into over-drive... causing the insects to die".... Just imagine they have altered your genes so that testosterone could not be created... so you will never feel the need to reproduce or to jerk off. (how sad that would be... as sex is most sought after activity on the net. Genealogy/family search is 2nd interestingly )
Germany have kicked out companies creating GMO in foods. But in the US the FDA is in bed with GMO companies to make corn (saw King Corn the documentary, anyone? ) soy, cotton, etc... These companies are also blocking bills to label foods as GMO ... so be very aware... I only eat organic food, and I grow a lot of my herbs ... they don't need much soil and grow easily in pots.
But some GMO organism are useful in understanding diseases. Labs around the worlds have created glow-in-the-dark cats, mice, dogs, and monkeys species... Koreans are obsessed with genetics as they have created the first glow in the dark dogs (Saw the movies "The Islands" with Ewan McGregor any one? It score big there relatively to every where else. Don't be surprised if the Chinese will clone the first super soldier to take over Asia and then the world.
Playing with GMOs are like playing with nuclear weapons in the WW2 area ( way to go...Let's nuke innocent civilians, babies, kids, grandmothers... and by the way, we need to nuke half the state of New Mexico and store the nuclear waste in Nevada for next half million years...so said the god damn politicians)
... SO GMOs are new, fun, get-to-play god...it's exciting, it's get attention... BUT it can also extinct species and the human race along ... GMO crops and pesticides have been tied to millions of disappeared bee colonies.. guess what? Monsanto just bought the company of scientist trying to study the disappearing bees (to put them out of business or to shut them up)
... There are other ways to stop mosquito diseases, although more expensive, like breed more bats, or fish that eats mosquito larvae - just look to permaculture.... BTW, people may not have salmon to eat soon, if GMO salmons escape to the wild and create self destruct salmons, or salmon that taste like ... farmed-raised salmon ... yuck... ... I'm forced to go vegetarian to maintain the highest integrity of my food ... although I love wild salmon sashimi...BOTTOM LINE: be careful with GMOs