To date, the UDN has discovered and
published papers on two new disease
genes, NACC1 and IRF2BPL. After
identifying these genes in children, they
were able to track down other affected
patients. They have also diagnosed a
patient with a variant in the KCNC1 gene,
known to cause progressive myoclonic
epilepsy. Because of that diagnosis, the
patient is now enrolling in a clinical trial
at another institution that could lead to
a drug trial specific to her gene variant.
The majority of UDN patients come
from the United States, but interna-
tional patients are accepted as long
as they can afford to travel. Patients
apply with suspected auto-immune
diseases, infectious diseases, rheuma-
tological diseases, genetic diseases and
neurological diseases – although it is
not often clear which category they fit
into when they first visit the UDN.TYPICALLY, THE UDN HAS A DIAGNOSIS
rate of 30 per cent, with the Duke site
slightly higher at 40 per cent. Because
of the rarity of so many conditions,
this percentage represents a signif-
icant accomplishment. However, the
reality is that most patients will never
receive a diagnosis. “Most patients
tell us that they expect not to get an
answer, because they have already been
through so many tests elsewhere,” says
Shashi. “They come in with the idea
that this is their last hope, and they’ll be
surprised if they get an answer.”
Holly, 47, is still waiting. Five years
ago, she began experiencing pain in theBelow: Genetic counsellor Heidi Cope: “When a variant is very rare, we think there’s a chance it could be disease-causing”bottom of her feet, which then spread
to her legs and quads. She saw an
orthopaedist, then a rheumatologist,
and eventually a neurologist, who
performed tests that suggested a
muscle disease but didn’t result in a
specific diagnosis. He suggested that
she would be a good candidate for the
UDN, and she underwent her first round
of UDN tests in the summer of 2018.“I was very hopeful when I got in touch
with the UDN,” Holly says. “I was excited
to have someone take a deeper look,
to try to make sure they encompass
everything they felt might be to
blame, and to have so many different
specialists looking at different angles.”
But full genome sequencing, blood
work and a skin biopsy revealed no
new information. A year later, Holly11-19-FTUndiagnosedDiseases.indd 142 10/09/2019 06:42