Introduction
X-linked
ID type Nascimento (XLID), characterized by a syndromic intellectual
disability due to gene mutation on the X chromosome, has great attention
caused by the high incidence rate of males in intellectual disability
[1-5].
According
to recent reports, almost 15 percent of the X-chromosome genes that is
known to be related to intellectual disability, while only accounts for
about 5 percent of the human genome[6]. However, the majority of
mutations in XLID genes remain unknown.
Ubiquitin-conjugating
enzyme E2 (UBE2A), involved in the proteasome pathway of protein
degradation and DNA repair [7], is located on Xq24 [8-10].
UBE2A
deficiency
syndrome, also known
as
X-linked ID type Nascimento (MIM #300860), was first described by
Nascimento in 2006, which was characterized clinically by pronounced
retardation of psychomotor development,
wide face, synophrys, generalized
hirsutism, urogenital abnormalities [11].
Since then, two splice-site
mutations in UBE2A, seven missense mutations in UBE2A, and four larger
deletions in UBE2A have been found [7, 12].
However,
there have been fewer reports of UBE2A splice site mutation in china.
Here, we report a Chinese patient
diagnosed with
XLID, and a novel UBE2A splice site
mutation (c.241+1 G>A).
In
addition to the clinical features of white matter abnormalities in MRI
and a recognizable face like wide faces are the same as the typical
features reported in XLID. Moreover, the novel clinical features of
erected head unstable, no hirsutism, no synophrys,healthy heart, were
found. Taken together, the finding of novel mutations of UBE2A in XLID
will be better to prevent disability in humans and more possibility to
explore the molecular basis of
intellectual disability.