2009 Vienna - European Society of Human Genetics
2009 Vienna - European Society of Human Genetics
2009 Vienna - European Society of Human Genetics
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Molecular basis <strong>of</strong> Mendelian disorders<br />
morphism and all types mutation have a discernible impact in human.<br />
The classes <strong>of</strong> mutations causing PMD are mainly duplications <strong>of</strong> the<br />
whole gene and point mutations.<br />
The purpose <strong>of</strong> this study is to analyse types <strong>of</strong> the PLP1 gene mutations<br />
among Polish PMD patients and compare the clinical picture in<br />
the context <strong>of</strong> the causative mutation.<br />
The molecular analysis <strong>of</strong> the PLP1 gene was performed according to<br />
general guidelines starting with gene dosage screening (MLPA method)<br />
followed by direct sequencing for patients withought rearrangements.<br />
Any type <strong>of</strong> PLP1 changes were described in 37% <strong>of</strong> probands.<br />
The duplication <strong>of</strong> all PLP1 exons was confirmed for four patients presenting<br />
different clinical picture (except brothers). We expected that<br />
the gene dosage might be modified by different size <strong>of</strong> duplication. To<br />
define more precisely the duplicated region aCGH was performed.<br />
The impact <strong>of</strong> discovered missense mutations on PLP1 protein structure<br />
and functional changes were analysed by in silico modelling.<br />
Analyses comprise the group <strong>of</strong> PMD male patients; four (2 unrelated<br />
,2 brothers) with duplication <strong>of</strong> the whole PLP1 gene, two patients<br />
(brothers) with nonsense mutation in Ex3 and two unrelated patients<br />
with missense mutations in different exons<br />
P12.129<br />
mutations spectrum in the stK11 gene in Polish Peutz- Jeghers<br />
syndrome patients<br />
W. Cichy 1 , M. Podralska 2 , M. Skrzypczak 2 , D. Nowakowska 3 , T. Banasiewicz 1 ,<br />
P. Krokowicz 1 , M. Teisseyre 4 , E. Czkwanianc 5 , R. Slomski 6 , B. Niedoszztko 7 , A.<br />
Plawski 2 ;<br />
1 University <strong>of</strong> Medical Sciences, Poznan, Poland, 2 Institute <strong>of</strong> <strong>Human</strong> <strong>Genetics</strong>,<br />
Poznan, Poland, 3 Institute <strong>of</strong> Oncology, Warszawa, Poland, 4 Children’s Memorial<br />
Health Institute, Warszawa, Poland, 5 Institute <strong>of</strong> Polish Mother’s Memorial<br />
Hospital, Poznan, Poland, 6 Instytitute <strong>of</strong> <strong>Human</strong> <strong>Genetics</strong>, Poznan, Poland,<br />
7 University <strong>of</strong> Medical Sciences, Gdansk, Poland.<br />
Peutz-Jeghers syndrome (PJS) is rare, genetically conditioned disease.<br />
PJS is heredited in autosomal dominant manner and is characterized<br />
by occurrence <strong>of</strong> hamartomatous polys. The hamartomatous<br />
polyps are manifested during second or third decade <strong>of</strong> life. Occurrence<br />
hamartomatous polys in PJS may cause <strong>of</strong> many gastrointestinal<br />
discomforts. Although in PJS patients the risk <strong>of</strong> malignant<br />
transformation is lower then others hereditary neoplastic disease, an<br />
increased risk to development malignancies such as the pancreas, the<br />
breast, female and male reproductive organs is observed. The second<br />
characteristic manifestations <strong>of</strong> JPS are brown, dark or blue spots.<br />
PJS is caused by mutations in the STK11 on chromosome 19. STK11<br />
gene encodes a serine/threonine protein kinase participating in very<br />
important cell signaling pathways. We present study considering 20<br />
patients diagnosed with PJS. PJS diagnosis was based on presence<br />
<strong>of</strong> two or more polyps, or one polyp and typical pigmented lesions, or<br />
one polyp and a family history <strong>of</strong> PJS. Mutations screening analysis<br />
encompassing SSCP, HA and direct sequencing <strong>of</strong> the LKB1gene are<br />
reveled five mutations and one polymorphism. These mutations are<br />
located in different position in gene (1, 2, 7 exons). With the Multiplex<br />
Ligation-dependent Probe Amplification (MLPA) - assay we detected<br />
additional genomic mutations. For our screening we used the SALSA<br />
P101 STK11 kit which contains MLPA probes for most STK11 exons. In<br />
four patients we identified exonic deletions or duplications range from<br />
one to five exons<br />
The study was financed by the Polish Ministry <strong>of</strong> Science and Higher<br />
Education project no. N401014435<br />
P12.130<br />
molecular analysis <strong>of</strong> most common mutations in Phenylalanine<br />
hydroxylase gene in iranian population<br />
S. Zare Karizi 1,2 , G. R. Javadi 1 , S. Zeinali 3 , M. Mazinani 2 ;<br />
1 Islamic Azad University Science and Research Campus, Tehran, Islamic Republic<br />
<strong>of</strong> Iran, 2 National Institute for Genetic Engineering and Biotechnology,<br />
Tehran, Islamic Republic <strong>of</strong> Iran, 3 Biotechnology Research Center , Pasteur<br />
Institute <strong>of</strong> Iran, Tehran, Islamic Republic <strong>of</strong> Iran.<br />
Phenylketonuria (PKU) is the most prevalent disorder <strong>of</strong> amino acid<br />
metabolism. It is one <strong>of</strong> the most important preventable causes <strong>of</strong><br />
mental retardation. Incidence <strong>of</strong> PKU in Iran has been estimated at 1<br />
in 3600-4000 births. The same is true <strong>of</strong> turkey. PKU is an autosomal<br />
recessive disorder and it is caused by a deficiency <strong>of</strong> hepatic phenylalanine<br />
hydroxylase enzyme. To date several hundred mutations caus-<br />
ing PKU have been characterized in the PAH gene.<br />
The aim <strong>of</strong> this study is to assess the prevalence <strong>of</strong> PKU mutations in<br />
Iranian population. For this purpose, 150 unrelated patients with classic<br />
PKU (300 alleles) were screened for 10 mutations (IVS10-11g>a,<br />
R252W, R261X, R261Q, IVS11nt1, R408W, R408Q, L333F, 364delG<br />
and S67P) using polymerase chain reaction-restriction fragment length<br />
polymorphism. The predominant mutations in this population sample<br />
are IVS10-11g>a, R261Q, IVS11nt1 and R252W with the frequency<br />
21.7%, 9%, 6.7% and 4.7% respectively. In addition, 6 other mutations<br />
have been identified at relatively low frequencies (R261X (4%),<br />
364delG (3.7%), L333F (2%), R408W, R408Q and S67P (0.33%)).<br />
These informations provide a good basis for direct DNA diagnosis <strong>of</strong><br />
PKU in this population.<br />
P12.131<br />
case report: 6-year old girl with porencephaly, cataract and<br />
microhematuria caused by a de novo missense mutation in<br />
COL A gene<br />
K. Õunap 1,2 , R. Teek 1,3 , P. Rizzu 4 , R. Rein 5 , E. Sistermans 4 , M. S. van der<br />
Knaap 6 ;<br />
1 Department <strong>of</strong> <strong>Genetics</strong>, United Laboratories,Tartu University Hospital, Tartu,<br />
Estonia, 2 Department <strong>of</strong> Pediatrics, University <strong>of</strong> Tartu, Tartu, Estonia, 3 Department<br />
<strong>of</strong> Oto-Rhino-Laryngology, University <strong>of</strong> Tartu, Tartu, Estonia, 4 Section<br />
Medical Genomics, Department <strong>of</strong> Clinical <strong>Genetics</strong>, VU University Medical<br />
Center, Amsterdam, The Netherlands, 5 Children’s Clinic, Tartu University Hospital,<br />
Tartu, Estonia, 6 Department <strong>of</strong> Child Neurology, VU University Medical<br />
Center, Amsterdam, The Netherlands.<br />
Porencephaly is heterogeneous anomaly and usually caused by an<br />
ante- or perinatal parenchymal insult in the brain. More recently, the<br />
role <strong>of</strong> mutations in the COL4A1 gene has been shown as a one cause<br />
<strong>of</strong> familial porencephaly. More than 20, mostly familial cases have<br />
been previously published. Here we describe an additional case.<br />
This patient was repeatedly investigated due to porencephaly and<br />
cataract since birth. Symptomatic focal epilepsy, microcephaly (-3SD)<br />
and unspecified microhematuria were additionally noticed. Congenital<br />
cytomegalovirus infection was firstly diagnosed, but could not be confirmed<br />
by DNA analysis on the newborn screening card. Brain MRI investigation<br />
showed bilateral porencephaly with a dark rim in the border<br />
<strong>of</strong> these areas indicating preceding hemorrhage; in other brain areas<br />
dark spots were seen, suggestive <strong>of</strong> hemosiderin deposition and damaged<br />
basal ganglia. Second MRI investigation showed additionally a<br />
signal abnormality in the hilus <strong>of</strong> the dentate nucleus. All those findings<br />
were suggestive to a mutation in COL4A1 gene.<br />
The COL4A1 gene was analyzed by sequencing analysis and a de<br />
novo missense mutation was found: c.3707G>A (p.Gly1236Glu). This<br />
mutation is likely pathogenic as it is a mutation that changes a highly<br />
conserved Gly residue within Gly-Xaa-Yaa repeats in the triple helix<br />
domain. Changes in this conserved element are likely to impair the triple<br />
helix formation during collagen assembly. It is shown that COL4A1<br />
mutation carriers have great diversity in the clinical expression within<br />
the same family. Our described case is showing that the diagnosis<br />
should also be considered in sporadic cases <strong>of</strong> porencephaly.<br />
P12.132<br />
Recessive primary congenital lymphoedema caused by a<br />
VEGFR3 mutation<br />
M. Vikkula 1 , A. Ghalamkarpour 1 , W. Holnthoner 2 , P. Saharinen 2 , L. Boon 3 , J. B.<br />
Mulliken 4 , K. Alitalo 2 ;<br />
1 Laboratory <strong>of</strong> <strong>Human</strong> Molecular <strong>Genetics</strong>, de Duve Institute, UCL, Brussels,<br />
Belgium, 2 Molecular/Cancer Biology Laboratory and Ludwig Institute for Cancer<br />
Research, Biomedicum Helsinki, Haartman Institute and Helsinki University<br />
Central Hospital, University <strong>of</strong> Helsinki, Helsinki, Finland, 3 Laboratory <strong>of</strong> <strong>Human</strong><br />
Molecular <strong>Genetics</strong>, de Duve Institute, UCL and Centre for Vascular Anomalies,<br />
Cliniques universitaires Saint-Luc, Brussels, Belgium, 4 Vascular Anomalies<br />
Center, Department <strong>of</strong> Plastic Surgery, Children’s Hospital, Harvard Medical<br />
School, Boston, MA, United States.<br />
The aetiology for primary congenital lymphoedema is not well known.<br />
Heterozygous mutations in VEGFR3 have been identified in some familial<br />
cases with dominant inheritance, known as Nonne-Milroy disease.<br />
Recessive cases <strong>of</strong> primary lymphoedema with a genetic cause<br />
are not known, except for two families with syndromic hypotrichosislymphoedema-telangiectasia,<br />
with a SOX18 mutation. In this study, we<br />
present the first case <strong>of</strong> isolated primary congenital lymphoedema with