2008 Barcelona - European Society of Human Genetics

Molecular and biochemical basis of disease
sampling . The 2 other patients were from consanguineous parents,
and were homozygous for a previously described p .Leu481Gln mutation
and a frameshift mutation resulting from a 2bp duplication, respectively
.
P05.100
A new syndrome with infantile-onset spasticity, mental
retardation and abnormalities of white matter and cerebellum in
a large consanguineous family.
A. J. M. H. Verkerk 1 , R. Schot 2 , B. Dumee 1 , S. Swagemakers 1 , M. W. Wessels
2 , K. Schellekens 1 , A. Bertoli 2 , M. Kros 3 , M. H. Lequin 4 , J. Dudink 4 , R. F. de
Coo 5 , R. Willemsen 2 , P. van der Spek 1 , G. M. S. Mancini 2 ;
1 Bioinformatics ErasmusMC, Rotterdam, The Netherlands, 2 Clinical Genetics
ErasmusMC, Rotterdam, The Netherlands, 3 Pathology ErasmusMC, Rotterdam,
The Netherlands, 4 Radiology ErasmusMC, Rotterdam, The Netherlands,
5 Child Neurology ErasmusMC, Rotterdam, The Netherlands.
We describe in a sibship of 11 children from consanguineous parents
2 apparently distinct disorders . Seven sibs suffer from autosomal recessive
arterial tortuosity syndrome (ATS) caused by a homozygote
GLUT10 mutation, as reported before (Coucke, Nat Genet, 2006) . We
classified the second disorder and report linkage studies to identify a
distinct recessive locus . Five sibs present with a neurodevelopmental
disorder, consisting of neonatal hypotonia, severe psychomotor
retardation, no independent deambulation, progression to tetraplegia,
excessive drooling, strabismus, no speech development, no signs of
denervation, no seizures and prolonged survival . The oldest patient
is 25 years old. Four of them have also ATS, but the fifth has no sign
of arterial tortuosity and is heterozygote for the familial GLUT10 mutation
. Brain MRI of this patient shows asymmetric widespread loss
of periventricular white matter with normal myelination and cerebellar
atrophy . MRI of the other neurologically affected sibs is similar, with
the addition of arterial tortuosity. Brain autopsy of one of the five sibs
who died of aspiration shows signs of neuro-axonal dystrophy . DTI and
fiber track data analysis from MRI suggest a combined neuron and
myelin damage . We undertook linkage analysis for a second recessive
locus in these five sibs and excluded loci for known white matter disorders,
spastic paraplegias and infantile neuroaxonal dystrophy . We
found instead linkage for a new chromosomal locus . We conclude that
the neurological disorder in this family represents a new type of early
onset upper motor neuron disease leading to early selective loss / under-development
of pyramidal tracts .
P05.101
investigation of cytokine expression pattern associated with the
pathogenesis of inflammatory bowel disease
D. IANCU1 , M. Diculescu2 , C. Iancu1 , E. Neagu1 , A. Constantinescu1 , C. Constantinescu1
, G. Girbea1 , L. Barbarii1 ;
1 2 National Institute of Legal Medicine, Bucharest, Romania, Fundeni Clinical
Hospital – Gastroenterology Department, Bucharest, Romania.
Inflammation is the shared pathophysiological element for the two main
inflammatory bowel diseases (IBD), Crohn’s disease (CD) and ulcerative
colitis (UC) but its contribution to the triggering and maintaining
the pathological condition is still incompletely understood . Our objective
was to investigate the pro-inflammatory gene expression profile in
colonic mucosa of IBD patients in order to establish correlations with
IBD form and disease activity .
RNA was extracted from colonic biopsy samples obtained from IBD patients,
after informed consent . The samples were initially screened for
inflammatory gene expression profile with a MLPA kit (SALSA R009,
MRC Holland) which allows detection of 40 RNA molecules in the
same PCR reaction . Subsequently, the selected mRNAs were quantified
using RT real-time PCR in individual gene expression assays. We
investigated a total of 50 patients with IBD, 33 with CD and 17 with
UC . Our preliminary results show an increased expression of some
monocyte-derived cytokines (IL1B, IL1RN, IL8, IL12, MIF) and some
inflammation associated transcription factors (NFkB, NFKBIA). The
cytokines’ expression pattern in apparently normal mucosa showed a
reduced but still significant inflammatory response.
P05.102
Regulatory elements at INS gene and Neonatal Diabetes
I. Garin 1 , J. Locke 2 , G. Pérez-Nanclares 1 , R. Martínez 1 , L. W. Harries 2 , L.
Castaño 1 , G. Pérez de Nanclares 1 ;
1 Endocrinology and Diabetes Research Group, Hospital de Cruces, Barakaldo,
Spain, 2 Department of Molecular Genetics, Royal Devon and Exeter Foundation
Trust, Exeter, United Kingdom.
Introduction: Insulin secretion is tightly regulated to maintain blood glucose
levels within a narrow physiological range . Recent studies have
reported heterozygous missense mutations at INS gene in permanent
neonatal diabetes (PND) . Multiple discrete sequence elements within
the proximal promoter region (5’UTR) affect insulin expression, and
also the 3’-untranslated (3’-UTR) region has been identified as critical
for murine preproinsulin mRNA stability .
Objective: To evaluate the putative contribution of INS in unrelated
subjects with unexplained neonatal diabetes (ND =14) .
Methods: the 3 exons (including untranslated exon 1), intron-exon
junctions and the 5’ and 3’ untranslated regions of INS were PCR amplified
with specific primers and direct sequencing was performed.
Results: No mutations were identified in the coding sequence. However,
we detected 5 novel variants . Three of them were situated in the
first exon:
- One patient presented 2 contiguous variants in compound heterozygosis
(c .[-332C>G]+[-331C>G]) .
- One patient carried a heterozygous variant (c .-170A>G) .
One patient presented an intronic variant (c .188-31G>A) which was
inherited from the father, who also presented with PND .
In a patient with PND a homozygous variant was detected in the 3’UTR
(c .*59A>G) . Both parents carried this variant and both presented with
glucose intolerance . This variant is situated at the 6 th nucleotide within
in the polyadenylation signal site; (AAAUAA - AAAUAG) .
Conclusions: Alterations in regulatory elements at INS are associated
with an earlier onset of PND compared to previously described coding
mutations . Mutations in the insulin gene are rare in Spanish patients
with neonatal diabetes .
P05.103
FoxP3 expression on different stage of type 1 diabetes mellitus
P. V. Apanovich1 , T. V. Nikonova2 , T. A. Muzaffarova1 , M. V. Shestakova2 , A. V.
Karpukhin1 ;
1 2 Research Centre For Medical Genetics, Moskow, Russian Federation, Endocrinological
Research Center, Moskow, Russian Federation.
FoxP3 expression is considered as key factor for autoimmunity preventing
. It is known that FoxP3 expression level is decreased under
type 1 diabetes mellitus . However there no information about the expression
level on different stage of this disease .
We investigated FoxP3 expression among for the first time revealed
type 1 diabetes mellitus patients (up to 1 year, early disease stage)
and a group of patients throuhg 15-25 years after disease beginning
(late stage of disease) . FoxP3 expression level was determined comparative
to expression of GAPDH gene or CD4 gene expression level
by Real Time PCR . It was revealed that FoxP3 expression was increased
on late stage of disease relatively to early disease stage as
with GAPDH so CD4 genes . There were 0,32±0,13 on early disease
stage and 1,1±0,35 on late stage for FoxP3 expression level (P= 0,02) .
The increasing of FoxP3 expression may means the decreasing of
autoimmune reaction on advanced stage of diabetes. Possibly it reflect
equilibrium state of immunity and produced by β-cells antigene.
P05.104
The influence of the genetic polymorphisms on the transcription
factor binding to the iL-4 promoter.
Y. V. Gervaziev 1 , L. V. Olenina 2 , S. A. Mazurina 3 , V. B. Gervazieva 3 ;
1 V.N. Orekhovich’s Institute of Biomedical Chemistry RAMS, Moscow, Russian
Federation, 2 Institute of Molecular Genetics, Moscow, Russian Federation, 3 I.I.
Mechnikov’s Institute of Vaccines and Sera RAMS, Moscow, Russian Federation.
Background: Promoter polymorphisms of IL-4 gene C-33T and C-
590T are well described. They influence both IL-4 and serum IgE concentrations
in a human organism . Objective: To evaluate the mechanism
of the phenotypic effect of these polymorphisms, specifically to
identify the transcription factors (TF) selectively binding to these loci .
methods: Sequences flanking these loci were analyzed in silico to