It is mysterious that it is not prohibited by law due to birth defects, learning disabilities, visual impairment, etc.

Some may think that the marriage of cousins, the so-called ' Itoko Marriage, ' is limited to the old royal aristocrats, but in Japan, where Itoko marriage is not prohibited by law, it is relatively recent. It seems that there are surprisingly many people who are married to Cousin, such as the late writer Takehiro Irokawa (Tetsuya Asada) and Mrs. Takako, and Prime Minister Naoto Kan and Mrs. Nobuko.

Looking at the treatment of cousin marriage in other countries, there are states (25 states) where cousin marriage is prohibited depending on the state in the United States, but it is not particularly prohibited in the United Kingdom. However, in Western countries, it tends to be seen as taboo, and conversely, in some areas such as the Islamic world, cousin marriage is rather preferred. In the United Kingdom, where cousin marriages are on the rise in Pakistani and other immigrant communities in recent years, the shocking reality is that as many as 700 children from cousin marriages are born with genetic disorders each year.

700 children born with genetic disabilities due to cousin marriages every year
https://www.telegraph.co.uk/news/health/news/7957808/700-children-born-with-genetic-disabilities-due-to-cousin-marriages-every-year.html

More than half of Pakistani British are married to their cousins, and Pakistani children are 10 times more likely to be born with a genetic disorder than the general population.

Risks associated with Itoko marriage include an increased infant mortality rate for the child born and an increased probability of birth defects (congenital defects), learning disabilities , visual impairment , hearing loss, and metabolic disorders. In addition, when a child born in a cousin marriage becomes an adult, the risk of infertility or miscarriage is higher than in general, and one-third of the children will die by the fifth birthday.

A study of the Channel 4 documentary Dispatches found that more than 70 studies in the United Kingdom proved the risk of cousin marriage, with as many as 700 British Pakistani children born each year with a genetic disorder. Nevertheless, it has become clear that people are ignoring this danger.

Former Parliamentarian Ann Cryer, from the Labor Party 's Keighley district, has received a lot of resistance as he tried to shed light on the issue.

'This is a public health issue, and like other issues such as obesity, drug addiction, and alcohol, it should be addressed by raising public awareness and debate. But for some reason, Itoko marriage is a matter of concern. 'It's a delicate issue and shouldn't be touched,' said Ann Cryer, a former parliamentarian. 'It's weird. To find a solution, we should discuss it first.'

Research shows that the number of cousin marriages in the United Kingdom has increased dramatically over the last three decades. Itoko marriages between British Pakistanis are the main contributors to this increase, but there are some Bangladeshi and Middle Eastern and East African communities where nearly a quarter of the population marries with cousins. However, it seems that many cousin marriages are seen.