‘Hypertension is racist and sexist’: Scientists find genetic mutations put Europeans more at risk - and Chinese women get off scot-free

Paper by Chinese team offers clues as to why Asian women live longer

PUBLISHED : Monday, 02 November, 2015, 3:56pm
UPDATED : Monday, 02 November, 2015, 4:02pm

Most genetic mutations linked to hypertension in Europeans cannot be found in populations of Chinese people, according to a new study by Chinese researchers.

The finding comes after another recent study showed that 10 genetic changes seen in Caucasians from the continent are tied to hypertension, or abnormally high blood pressure.

But these same mutations do not typically apply to Chinese, and when they do the subjects are almost always male, the Chinese team said.

Hypertension raises the risk of heart disease and can shorten people’s life expectancy.

To learn more about how Chinese are affected, a research team with the Kunming Institute of Zoology at the Chinese Academy of Sciences in the southern province of Yunnan screened over 1,700 patients from two Chinese provinces.

From the aforementioned pool of 10, only one was found among Han Chinese, who make up over 90 per cent of the population on the mainland.

Tagged “rs4746172,” it occurred in a gene that plays an important role in the development of the embryo and certain heart functions through a process known as single nucleotide polymorphism.

The results “revealed a significant genotypic association of rs4746172 with hypertension... in male subjects but not in females,” said their paper, which was published in the journal Scientific Reports.

“That teaches us a couple of things,” said He Yonghan, who contributed to the paper. He is based at the same institute’s State Key Laboratory of Genetic Resources and Evolution in Kunming.

“Hypertension is not only racist, but sexist,” he said.

Researchers have long been intrigued as to why Asian populations generally exhibit lower levels of blood pressure than Caucasians in Europe and America.

One in every three adults suffers from hypertension in the United States at some point in their life, while the corresponding rate among Chinese is about one in four, according to previous studies.

But determining which genes made the difference was a challenge, He said.

A number of environmental elements can trigger high blood pressure, such as an unhealthy diet, work pressure or lack of regular exercise. Such variables make the screening process more complicated.

Gender differences add another layer of complexity. Women tend to live longer, with less risk of heart disease at an early age.

He described the discovery of the genetic mutation as a “blessing” as it sheds some light on the issue.

“It means men are more likely to get the mutation that will lead to high blood pressure,” He said.

“It could be a possible explanation why females have a lower chance of cardiovascular disease and, subsequently, live longer.”

The discovery could also spell good news for pharmaceutical companies.

“Most drugs aimed at easing hypertension in the market today are effective for certain people but not for other. The findings of our study will help develop patient-specific treatments,” He added.

But it could take years before medicines become available based on the discovery, pundits say.

One shortcoming of the latest study is that it is based on limited samples from Guangdong and Jiangsu. Scientists said the test pool would need to be larger to produce more reliable results.

Other factors such as the subject’s salt and alcohol intake may also compromise the results.