Andrew Sabisky, 27, answered Downing Street’s calls for ‘weirdos and misfits’ to advise Boris Johnson’s government, but his extreme views have sparked outrage online.

The self-titled ‘superforecaster’ made comments about the IQs of black people on a blog post published in 2014, which is now being circulated on social media.

He wrote: ‘If the mean black American IQ is (best estimate based on a century’s worth of data) around 85, as compared to a mean white American IQ of 100, then if IQ is normally distributed, you will see a far greater percentage of blacks than whites in the range of IQs 75 or below, at which point we are close to the typical boundary for mild mental retardation.

‘That parsimoniously explains the greater diagnostic rates for blacks when it comes to “Intellectual Disability”.

‘It [is] simply a consequence of the normal distribution of cognitive ability, because there are significant differences in the group means.’

Mr Sabiksy has also come under fire for previously stating that much of the ‘hue and cry’ against female genital mutilation ‘looks more like a moral panic’.

He also suggested that giving children mental performance-enhancing drugs, which pose a serious risk to life, is probably worth ‘a dead kid once a year’.

The Cambridge graduate also advocates for eugenics, which aims to improve the genetic quality of the population by excluding certain groups judged to be ‘inferior’.

In 2016, he said: ‘Eugenics are about selecting “for” good things.

‘Intelligence is largely inherited and it correlates with better outcomes: physical health, income, lower mental illness. There is no downside to having IQ except short-sightedness.’

The concept of eugenics was first started with Plato, but has been linked to Nazi Germany and white supremacists over the last century.

In 2014, Mr Sabisky also stated on Cummings’ website that a legal enforcement of contraception would help stop unplanned pregnancies in the UK.

pregnancies creating a permanent underclass would be to legally enforce universal uptake of long-term contraception at the onset of puberty.

‘Vaccination laws give it a precedent, I would argue.’

The aide is listed as a past speaker at a London Conference on Intelligence in 2015, which was also attended by white supremacists and far-right activists.

He also previously said women’s sport was ‘more comparable to the Paralympics than it is to men’s’ and dismissed female Labour politicians, including Angela Rayner and Rebecca Long Bailey, as ‘dim’.

Mr Sabisky’s comments are said to have also caused uproar among ministers, with reports of some preparing to boycott meetings where he is present.

Multiple special advisers told Buzzfeed they and their cabinet ministers will not be responding to emails from Mr Sabisky, and will tell Boris Johnson to sack him.

One former government special adviser told the publication: ‘Hiring this imbecile is an insult to those who came before, which is a minor point I know, but Jesus wept it makes me ashamed.’

Labour have also urged Johnson to sack Mr Sabisky, stating that there were ‘no words’ to describe his comments.