In a <link https: www.thelancet.com journals lancet article fulltext _blank external-link-new-window internal link in current>letter published in The Lancet, a group of British experts have warned that a no deal Brexit could result in the exclusion of the UK from the 24 European Reference Networks (ERNs) that work to improve the care of patients with rare diseases.  ERNs were set up because no one country has the expertise or resources to cover the thousands of rare diseases, and geneticists are particularly involved in the diagnosis and treatment of rare disease patients, and as such, with ERNs. « We would be saddened if, as a result of Brexit, the UK were to be excluded from ERNs in the future, and we believe this would be very harmful to British patients living with rare diseases. We hope sincerely that an acceptable solution may be found before the end of the year, when the change will come into effect, » said ESHG President-elect Professor Maurizio Genuardi.