By Lidia Zhelezovskaya
“In Europe, rare diseases are classed as those suffered by just one in 2,000 or more,” explains Konstantin Mosse who heads the Laboratory for Cytogenetic, Molecular-Genetic and Morphological Research at the Republican Mother and Child Scientific-Practical Centre. “Even the most widespread genetic diseases are considered rare; many are severe chronic diseases accompanied by life-threatening symptoms. These may be seen from the earliest age but might just as easily become apparent only in later childhood or adulthood.”
Four year old Polina, from Belarusian Novogrudok, has perplexed her parents and doctors from the first days of her life. Until recently, she was the only such case in the country, suffering from ‘Ondine’s Curse’ (the unofficial name for sleep apnea). Polina lacks autonomic control of her breathing while sleeping, so stops breathing independently each time she falls unconscious. As a baby, doctors were obliged to use artificial pulmonary ventilation to keep her alive. Today, she can breathe on her own, courtesy of a Swedish clinic which gave her an implanted diaphragm pacemaker. Sadly, no other cure exists for the defective gene responsible for her disease. “About 400 people worldwide suffer from ‘Ondine’s Curse’, with 90 percent featuring a new mutation. Others have inherited their illness,” says Mr. Mosse.
The Centre’s geneticists aim to detect the primary cause of each disease, so that they can determine whether someone is likely to be susceptible. Their equipment allows them locate all possible gene mutations, with special attention given to the most common pathologies (there are about 50 in Belarus). However, specialists are also ready to cope with others. “Often, we detect genetic defects responsible for neurological disease and metabolic irregularities. However, doctors’ prognoses do not always coincide with the real situation,” notes Mr. Mosse, adding, “For example, none of those whom we suspected of having Friedreich’s Ataxia had gene abnormalities (which lead to this pathology). Geneticists face a huge challenge in diagnosing rare diseases, since it’s impossible to identify a neurological pathology purely by molecular means. It takes time and money.”
Belarusian geneticists have already detected several hundred gene problems but still have much work to do to decipher the hidden secrets of our DNA. In fact, many people may not even realise that genes are the cause of their illness. Moreover, there are no more than ten specialists in our country qualified to conduct such research into DNA.
No effective treatment exists to cure the rarest diseases, although some drugs can improve our quality and length of life. Sadly, the most suitable approach — gene therapy — is not yet widely affordable. Some successful attempts have been made but their practical implementation remains out of reach. Mr. Mosse is sure that the future will see each ‘rare’ patient receiving the chance to regain full health, but who knows when that day may come.