Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients
Prader-Willi (PWS) and Angelman (AS) syndromes are two clinically distinct genetic diseases associated with multiple physical and cognitive abnormalities. The genetic cause of PWS and AS is the alteration in the 15q11.2-q13 chromosomal region; expression of genes in this region is subject to genome...
Gespeichert in:
| Datum: | 2018 |
|---|---|
| Hauptverfasser: | , |
| Format: | Artikel |
| Sprache: | English |
| Veröffentlicht: |
Інститут молекулярної біології і генетики НАН України
2018
|
| Schriftenreihe: | Вiopolymers and Cell |
| Schlagworte: | |
| Online Zugang: | http://dspace.nbuv.gov.ua/handle/123456789/154359 |
| Tags: |
Tag hinzufügen
Keine Tags, Fügen Sie den ersten Tag hinzu!
|
| Назва журналу: | Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| Zitieren: | Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients / S.Yu. Chernushyn, N.V. Hryshchenko // Вiopolymers and Cell. — 2018. — Т. 34, № 5. — С. 361-366. — Бібліогр.: 11 назв. — англ. |
Institution
Digital Library of Periodicals of National Academy of Sciences of Ukraine| id |
irk-123456789-154359 |
|---|---|
| record_format |
dspace |
| spelling |
irk-123456789-1543592019-07-07T12:26:19Z Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients Chernushyn, S.Yu. Hryshchenko, N.V. Biomedicine Prader-Willi (PWS) and Angelman (AS) syndromes are two clinically distinct genetic diseases associated with multiple physical and cognitive abnormalities. The genetic cause of PWS and AS is the alteration in the 15q11.2-q13 chromosomal region; expression of genes in this region is subject to genome imprinting. Aim. To analyse of the frequency of 15q11.2-q13 rearrangements and epigenetic alterations in the group of Ukrainian patients with PWS and AS. Methods. The methylation status of the SNRPN gene was analyzed by methylation-specific PCR (MS-PCR). Results. The absence of unmethylated CpGs in the SNRPN gene promoter was detected in 25 patients (42 %) with the PWS phenotype. In the AS group, the frequency of SNRPN mutations (absence of the hypermethylated CpGs) was observed in 28% of the cases. In the PWS, group we observed a significant prevalence of males (70 %), but the frequency of the confirmed diagnosis was higher in females (56% vs. 36%). A lower than expected detection rate in the PWS and AS groups could be due to both clinical and method limitations. Conclusions. Analysis of the SRNPN gene region by MS-PCR could be used for the PWS and AS molecular diagnostics. This test can rule out the clinical diagnosis of PWS in ~ 60 % of Ukrainian patients with suspected PWS and confirm AS in ~30% of patients. Синдроми Прадера-Віллі (СПВ) та Ангельмана (СА) – це різні за клінічними ознаками генетичні захворювання, які супроводжуються фізичними та когнітивними розладами. Генетичною причиною СПВ та СА є пошкодження в хромосомній ділянці 15q11.2-q13, експресія генів якої підлягає геномному імпринтингу. Мета. Оцінка частоти геномних перебудов та епігенетичних порушень в 15q11.2-q13 у групі пацієнтів з України, які мали фенотипові прояви СПВ та СА. Методи. Для одночасної детекції як генетичних, так і епігенетичних порушень, які призводять до СПВ та СА, аналізувався статус метилування гена SNRPN з використанням метил-специфічної ПЛР (МС-ПЛР). Результати. Порушення, яке призводить до СПВ – відсутність неметильованого гена SNRPN – було виявлено у 25 (42 %)хворих з фенотипом СПВ. В групі з СА частота мутацій SNRPN (відсутність гіпометильваного гена) виявлена у 28 % хворих. В групі з СПВ відмічено достовірне переважання пацієнтів чоловічої статі. Проте частка жінок з підтвердженим діагнозом в цій групі була вищою – 56 % проти 36 %. Менший за очікуваний відсоток підтвердження СПВ та СА може бути наслідком як помилок клінічної діагностики, так і методичних обмежень. Висновки. Аналіз ділянки гена SRNPN з використанням МС-ПЛР може бути запропонований для молекулярної діагностики СПВ та СА. Прогнозується, що використання цього методу тестування дозволяє виключити діагноз СПВ у приблизно 60 % хворих з клінічними ознаками цього синдрому, у 30 % пацієнтів з ознаками СА – підтвердити захворювання. Синдромы Прадера-Вилли (СПВ) и Ангельмана (СА) – это разные по клиническим признакам генетические заболевания, которые сопровождаются физическими и когнитивными расстройствами. Генетической причиной СПВ и СА является повреждение в хромосомной области 15q11.2-q13, экспрессия генов которой подлежит геномному импринтинуг. Цель. Оценка частоты геномных перестроек и эпигенетических нарушений в 15q11.2-q13 в группе пациентов с Украины с фенотипическими проявлениями СПВ и СА. Методы. Для одновременной детекций как генетических, так и эпигенетических нарушений, которые приводят к СПВ и СА, анализировался статус метилирования гена SNRPN с использованием метил-специфической ПЦР (МС-ПЦР). Результаты. Нарушение, которое приводит к СПВ – отсутствие неметильованого гена SNRPN – было обнаружено у 25 (42 %) больных с фенотипом СПВ. В группе с СА частота мутаций SNRPN (отсутствие гипометильваного гена) выявлено у 28% больных. В группе с СПВ отмечено достоверное преобладание пациентов мужского пола. Однако доля женщин с подтвержденным диагнозом в этой группе была выше – 56 % против 36 %. Меньший ожидаемого процент подтверждения СПВ и СА может быть следствием как ошибок клинической диагностики, так и методических ограничений. Выводы. Анализ участка гена SRNPN с использованием МС-ПЦР может быть предложен для молекулярной диагностики СПВ и СА. Прогнозируется, что использование этого метода тестирования позволяет исключить диагноз СПВ у примерно 60 % больных с клиническими признаками этого синдрома, у 30 % пациентов с признаками СА – подтвердить заболевания. 2018 Article Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients / S.Yu. Chernushyn, N.V. Hryshchenko // Вiopolymers and Cell. — 2018. — Т. 34, № 5. — С. 361-366. — Бібліогр.: 11 назв. — англ. 0233-7657 DOI: http://dx.doi.org/10.7124/bc.00098A http://dspace.nbuv.gov.ua/handle/123456789/154359 606:61+575.224.2+577.218+612.821.5+616-092 en Вiopolymers and Cell Інститут молекулярної біології і генетики НАН України |
| institution |
Digital Library of Periodicals of National Academy of Sciences of Ukraine |
| collection |
DSpace DC |
| language |
English |
| topic |
Biomedicine Biomedicine |
| spellingShingle |
Biomedicine Biomedicine Chernushyn, S.Yu. Hryshchenko, N.V. Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients Вiopolymers and Cell |
| description |
Prader-Willi (PWS) and Angelman (AS) syndromes are two clinically distinct genetic diseases associated with multiple physical and cognitive abnormalities. The genetic cause of PWS and AS is the alteration in the 15q11.2-q13 chromosomal region; expression of genes in this region is subject to genome imprinting. Aim. To analyse of the frequency of 15q11.2-q13 rearrangements and epigenetic alterations in the group of Ukrainian patients with PWS and AS. Methods. The methylation status of the SNRPN gene was analyzed by methylation-specific PCR (MS-PCR). Results. The absence of unmethylated CpGs in the SNRPN gene promoter was detected in 25 patients (42 %) with the PWS phenotype. In the AS group, the frequency of SNRPN mutations (absence of the hypermethylated CpGs) was observed in 28% of the cases. In the PWS, group we observed a significant prevalence of males (70 %), but the frequency of the confirmed diagnosis was higher in females (56% vs. 36%). A lower than expected detection rate in the PWS and AS groups could be due to both clinical and method limitations. Conclusions. Analysis of the SRNPN gene region by MS-PCR could be used for the PWS and AS molecular diagnostics. This test can rule out the clinical diagnosis of PWS in ~ 60 % of Ukrainian patients with suspected PWS and confirm AS in ~30% of patients. |
| format |
Article |
| author |
Chernushyn, S.Yu. Hryshchenko, N.V. |
| author_facet |
Chernushyn, S.Yu. Hryshchenko, N.V. |
| author_sort |
Chernushyn, S.Yu. |
| title |
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients |
| title_short |
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients |
| title_full |
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients |
| title_fullStr |
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients |
| title_full_unstemmed |
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients |
| title_sort |
study of snrpn genetic and epigenetic mutations in prader-willi and angelman patients |
| publisher |
Інститут молекулярної біології і генетики НАН України |
| publishDate |
2018 |
| topic_facet |
Biomedicine |
| url |
http://dspace.nbuv.gov.ua/handle/123456789/154359 |
| citation_txt |
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients / S.Yu. Chernushyn, N.V. Hryshchenko // Вiopolymers and Cell. — 2018. — Т. 34, № 5. — С. 361-366. — Бібліогр.: 11 назв. — англ. |
| series |
Вiopolymers and Cell |
| work_keys_str_mv |
AT chernushynsyu studyofsnrpngeneticandepigeneticmutationsinpraderwilliandangelmanpatients AT hryshchenkonv studyofsnrpngeneticandepigeneticmutationsinpraderwilliandangelmanpatients |
| first_indexed |
2025-07-14T05:59:32Z |
| last_indexed |
2025-07-14T05:59:32Z |
| _version_ |
1837600890560708608 |
| fulltext |
361
S. Yu. Chernushyn, N. V. Hryshchenko
© 2018 S. Yu. Chernushyn et al.; Published by the Institute of Molecular Biology and Genetics, NAS of Ukraine on behalf
of Biopolymers and Cell. This is an Open Access article distributed under the terms of the Creative Commons Attribution
License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted reuse, distribution, and reproduction in any
medium, provided the original work is properly cited
UDC 606:61+575.224.2+577.218+612.821.5+616-092
Study of SNRPN genetic and epigenetic mutations in Prader-Willi
and Angelman patients
S. Yu. Chernushyn, N. V. Hryshchenko
Institute of Molecular Biology and Genetics, NAS of Ukraine
150, Akademika Zabolotnoho Str., Kyiv, Ukraine, 03143
dnatest@imbg.org.ua
Prader-Willi (PWS) and Angelman (AS) syndromes are two clinically distinct genetic diseases
associated with multiple physical and cognitive abnormalities. The genetic cause of PWS and
AS is the alteration in the 15q11.2-q13 chromosomal region; expression of genes in this region
is subject to genome imprinting. Aim. To analyse of the frequency of 15q11.2-q13 rearrange-
ments and epigenetic alterations in the group of Ukrainian patients with PWS and AS. Methods.
The methylation status of the SNRPN gene was analyzed by methylation-specific PCR (MS-
PCR). Results. The absence of unmethylated CpGs in the SNRPN gene promoter was de-
tected in 25 patients (42 %) with the PWS phenotype. In the AS group, the frequency of SNRPN
mutations (absence of the hypermethylated CpGs) was observed in 28 % of the cases. In the
PWS, group we observed a significant prevalence of males (70 %), but the frequency of the
confirmed diagnosis was higher in females (56 % vs 36 %). A lower than expected detection
rate in the PWS and AS groups could be due to both clinical and method limitations. Conclusions.
Analysis of the SRNPN gene region by MS-PCR could be used for the PWS and AS molecular
diagnostics. This test can rule out the clinical diagnosis of PWS 30 % of patients.
K e y w o r d s: Prader-Willi Syndrome, Angelman Syndrome, SNRPN gene, methyl-specific
PCR.
Introduction
Prader-Willi syndrome (PWS) is characterized
by hypotonia, failure to thrive with poor suck,
hypogonadism, short stature with small hands
and feet, hyperphagia leading to morbid obe-
sity, beginning from early childhood; devel-
opmental delay/intellectual disability, and be-
havioral issues, including obsessive compul-
sive disorder. The characteristic facial features
are also evident. Angelman syndrome (AS) is
characterized by developmental delay, intel-
lectual disability, absent speech, seizures,
ataxic gait, easily excitable happy demeanor,
and characteristic faces.
PWS and AS typically result from the dele-
tion of paternal for PWS or maternal for AS
copies of the chromosome region 15q11-q13.
Biomedicine ISSN 1993-6842 (on-line); ISSN 0233-7657 (print)
Biopolymers and Cell. 2018. Vol. 34. N 5. P 361–366
doi: http://dx.doi.org/10.7124/bc.00098A
mailto:dnatest@imbg.org.ua
362
S. Yu. Chernushyn, N. V. Hryshchenko
Each one occurs with a frequency of approxi-
mately 1/15,000 to 1/30,000 live births [1], in
the vast majority of cases they happen de novo,
in families with no history of these syndromes.
Chromosome 15q11-q13 is a region that
harbors several genes regulated by genomic
imprinting, a phenomenon when genes are
expressed preferentially from one parental al-
lele. As a result, the genes subjected to regula-
tion by genomic imprinting are functionally
haploid, having only a single functional
copy [2]. At least two genes SNRPN and NDN
from the 15q11-q13 region have differentially
methylated CpG islands in their promoter re-
gions that are methylated on the maternal chro-
mosome leading to the silencing of the mater-
nal allele. The alteration of the paternal copy
of the imprinted SNRPN gene will cause
PWS [3], and vice versa, the loss of maternal
allele leads to AS. The other gene in this re-
gion, encoding the ubiquitin-protein ligase
E3A — UBE3A, is a parentally imprinted gene
in which the paternal allele is selectively si-
lenced in mature neurons. The promoter of
UBE3A gene is completely unmethylated and
it is active on both parental copies in all tis-
sues, silencing of the paternal allele expression
is achieved by noncoding antisense transcript
UBE3A-ATS [4], which is transcribed back-
wards to the UBE3A.
There are 4 known genetic mechanisms
which can cause PWS and AS: de novo dele-
tions involving the chromosome 15q11.2-q13
region, uniparental disomy (UPD) of 15q11.2-
q13, imprinting center (IC) defects and point
mutations in the causative gene (Table 1).
About 20 % of cases of AS are caused by
mutations in the UBE3A [5] but there are no
instances of a point mutation in any gene caus-
ing PWS, suggesting that PWS is a true con-
tiguous gene syndrome, resulting from the loss
of more than one gene.
Table 1. Genetic alterations lead to Prader-Willi
and Angelman syndromes [6]
Genetic mechanisms PWS AS
De novo deletions 75-80 % 70-75 %
UPD 20-25 % 3 %-7 %
IC mutations (excluding
deletions) 1-2 % 1-2 %
IC deletions 5-15 % 5-15 %
UBE3A mutations - 5-10 %
The deletion of the 15q11.2-q13 locus oc-
curs at a frequency of about 1/15,000 new-
borns and is probably one of the most common
pathogenic deletions observed in humans.
For molecular genetic diagnostics of PWS
and AS, the most commonly used method is
the analysis of the SNRPN gene using FISH [7].
This method allows identifying only deletions
in the studied region. Therefore, the use of
methods capable of detecting UPDs and meth-
ylation defects significantly increase the infor-
mativeness of the molecular diagnosis of these
syndromes.
The aim of the study was an estimation of
15q11.2-q13 rearrangements and epigenetic
alterations frequency in the group of Ukrainian
patients with PWS and AS clinical phenotype.
The analysis of the SNRPN gene alterations by
methyl-spesific PCR was chosen because it
allowed simultaneous testing of three types of
alterations: deletions, UPDs and IC defects.
Methods
Group of 60 Ukrainian patients with PWS
phenotype (18 females and 42 males) and 32
patients with AS phenotype (21 and 11 respec-
363
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients
tively) were referred from the regional medical
genetics centers of Ukraine to the IMBG from
2011 to the present. The informed consent for
clinical and genetic study was obtained from
the patients statutory trustees in compliance
with national ethics regulation.
DNA was extracted from the patients blood
samples using proteinase K cell lysis and stan-
dard phenol-chloroform DNA purification. To
identify methylation status of the SNRPN gene
all collected samples were analyzed by meth-
ylation-specific PCR (MS-PCR). Bisulfide
(BS) conversion of genomic DNA was carried
out using EZ DNA Methylation-GOLDTM Kit
(Zymo Research) according to the manufac-
turer’s protocol. We used 1–2 μg of genomic
DNA for BS- conversion, the converted DNA
was diluted in 10–15 μl of the elution buffer.
To find out the methylation status of the 15q11-
q13 locus we used PCR with two primers
pairs: one specific to the SNRPN gene BS-
converted methylated DNA, second — to the
SNRPN gene BS-converted unmethylated
DNA. PCR was carried out in a total volume
of 20 μl containing 1x FIREPol® Master Mix
with 2.5 mM MgCl2 (Solis BioDyne), 0.75μM
primers (both for the methylated and unmeth-
ylated BS-converted SNRPN gene fragments)
and 10μl of BS-converted DNA solution. The
PCR conditions were 1 cycle — 95°C for 5
min followed by 35 cycles of the 3 step pro-
tocol: 95°C — 20 sec, 62°C — 30 sec, 72°C —
30 sec. The MS-PCR results were visualized
by 1.5 % agarose gel electrophoresis and ethid-
ium bromide staining.
Results
The MS-PCR technique used in this work al-
lows the differential detection of both types of
normal alleles of the SNPRP gene (methylated
and unmethylated). The presence of two frag-
ments (174 and 100 bp) corresponds to the
presence of two normal homologues of the
15th chromosome: methylated, inherited from
the mother (174 bp) and unmethylated - from
the father (100 bp) (fig. 1). Thus, it is possible
to reveal the presence of a deletion in methy-
lated or unmethylated allele, a uniparent di-
somy (the presence of only 2 methylated or
only 2 unmethylated alleles) and mutations in
IC, leading to the absence of one or another
type of allele. Based on the literature data
presented in Table 1, PWS can occur only as
a result of 3 types of alterations of the 15q11.2
chromosomal region: paternal deletions, ma-
ternal uniparent disomy or mutations in the IC.
So, the analysis of the SRNPN gene by MS-
PCR could detect about 100 % of the altera-
tions associated with PWS. Considering that
in a third of cases AS is caused by the UBE3A
mutations, the informativeness of the MS-PCR
for this disease does not exceed 70 %.
Additionally, one of the disadvantages is that
this method, identifying 3 types of damage,
does not allow their differentiation.
Fig. 1. Analysis of the SNRPN gene in PWS and AS sam-
ples by MS-PCR, 1.5 % agarose gel: 1,4 — patients with
PWS; 2 — patient with normal methylation; 3 — patient
with AS; 5 — ladder 100 bp.
364
S. Yu. Chernushyn, N. V. Hryshchenko
In the analyzed group of 60 patients with
suspected PWS phenotype the absence of an
unmethylated allele of the SNRPN gene was
observed in 42 % of patients. These 25 patients
have one of three possible genetic causes of
PWS: paternal deletions, maternal UPDs or IC
alterations of SNRPN.
In the AS group the frequency of SNRPN
methylated allele loss was detected in 28 % (9
of 32) of patients. There are also 3 possible
genetic causes — maternal deletions/paternal
UPDs/IC, but the most likely one, based on
literary data, is the deletion in the 15q11.2 of
maternal origin.
Discussion
The deletions of the chromosome 15q11.2–q13
region are typically diagnosed by fluorescence
in situ hybridization (FISH) using the SNRPN
probe [7]. With this method, it is possible to
confirm the diagnosis in 60–70 % of PWS and
AS patients, but not those caused by UPDs or
IC defects.
Based on the results obtained, it can be
argued that the application of the MS-PCR
technique to verify PWS is the most informa-
tive and low-cost in comparison with the FISH.
However, in our study, close to 100 % confir-
mation of PWS was not obtained. Lower than
expected detection rate in the PWS group can
be explained by the presence of patients with
PWS-like syndromes. We can assume that
proximal spinal muscular atrophy type I (SMA
I, OMIM # 253300) may be one of the prob-
able diseases in children younger than
18 months when PWS was not confirmed. Both
of these diseases SMA I and PWS are charac-
terized by generalized hypotonia at the age of
12–18 months [8–9]. In case of PWS, these
symptoms do not progress and are fade away
when a patient reached the second year of life,
in contrast to SMA I. This may be confirmed
by the fact that in one patient with suspected
PWS, we identified homozygous deletions in
the SMN1 gene, which are major mutations in
SMA I. Therefore, it is possible to recommend
additional clinical and genetic studies to the
patients under 18 months, who have idiopath-
ic hypotonia, for differentiation of the diagno-
sis. Among clinical studies, the most informa-
tive, in our opinion, may be electromyography,
which allows detecting muscular and neural
alterations that lead to muscular or neuronal
hypotonia and are not associated with PWS.
Moreover, in the PWS group we observed
the significant prevalence of males — 70 % (42
of 60), but the frequency of detected alterations
in females was higher than in males — 56 %
(10 of 18 patients) and 36 % (15 of 42) cor-
respondently. This can indicate that less strict
diagnostic criteria for males lead to incorrect
over diagnostics of PWS in the current group.
The low detection rate in AS (28 %) could
be due to both clinical misdiagnosis and limita-
tions of the used method of molecular ana lysis.
To improve the molecular diagnostics of AS,
the further analysis of the AS associated genes,
such as the UBE3A and MECP2 genes should
be done. We suggested that in addition to the
mutations in the UBE3A gene, the mutations in
the MECP2 gene can lead to the AS phenotype.
This assumption is based on the literature data
about the similarity of the clinical phenotype in
the patients with Rett syndrome and AS [10, 11].
Conclusions
Analysis of the SRNPN gene region by MS-
PCR is cost-effective and high informative,
365
Study of SNRPN genetic and epigenetic mutations in Prader-Willi and Angelman patients
therefore it could be implemented for the PWS
and AS molecular diagnostics, rather than
FISH. Our results revealed that the proposed
molecular test can exclude the clinical diag-
nosis of PWS in approximately 60 % of
Ukrainian patients with suspected PWS. In
30 % of the suspected AS patients, this analy-
sis confirms the clinical diagnosis. Our near-
term plans include implementation of further
molecular analysis of the AS associated genes,
such as the UBE3A and MECP2 genes, to
improve the detection rate of molecular diag-
nostics of AS.
Acknowledgements
The authors would like to thank all clinical
specialists from regional the medical genetic
centers of Ukraine, for their participation in
the survey of patients, support providing pa-
tients’ samples and phenotype information. We
wish to acknowledge the help in the method-
ological issues provided by Prof. Igor Lebedev
and Prof. Ludmila Livshits, who supported the
study planning, academic and technical staff
of our department for their assistance. We are
also grateful to the patients and members of
their families for their kind consent to partici-
pate in the study.
REFERENCES
1. Kalsner L, Chamberlain SJ. Prader-Willi, Angelman,
and 15q11-q13 Duplication Syndromes. Pediatr Clin
North Am. 2015;62(3):587–606.
2. Choufani S, Weksberg R. Genomic imprinting. Funct
Nucl. 2016; 4(1): 449–65.
3. Sharp AJ, Migliavacca E, Dupre Y, Stathaki E,
Sailani MR, Baumer A, Schinzel A, Mackay DJ,
Robinson DO, Cobellis G, Cobellis L, Brunner HG,
Steiner B, Antonarakis SE. Methylation profiling in
individuals with uniparental disomy identifies no vel
differentially methylated regions on chromosome
15. Genome Res. 2010;20(9):1271–8.
4. LaSalle JM, Reiter LT, Chamberlain SJ. Epigenetic
regulation of UBE3A and roles in human neurodevel-
opmental disorders. Epigenomics. 2015;7(7):1213–28.
5. Kishino T, Lalande M, Wagstaff J. UBE3A/E6-AP
mutations cause Angelman syndrome. Nat Genet.
1997;15(1):70–3.
6. Ramsden SC, Clayton-Smith J, Birch R, Buiting K.
Practice guidelines for the molecular analysis of
Prader-Willi and Angelman syndromes. BMC Med
Genet. 2010;11:70.
7. Smith A, Robson L, St Heaps L. Use of two FISH
probes provides a cost-effective, simple protocol to
exclude an imprinting centre defect in routine labo-
ratory testing for suspected Prader-Willi and Angel-
man syndrome. Ann Genet. 2002;45(4):189–91.
8. Elsheikh BH, Kissel JT. Spinal Muscular Atrophies.
In: Eds. Katirji B, Kaminski H, Ruff R. Neuromus-
cular Disorders in Clinical Practice. Springer, New
York, NY;2014:425–39.
9. Puiu M, Cucu N. Prader – Willi Syndrome, from
Molecular Testing and Clinical Study to Diagnostic
Protocols. Rijeka: “InTech”, 2011; 472 p.
10. Watson P, Black G, Ramsden S, Barrow M, Super M,
Kerr B, Clayton-Smith J. Angelman syndrome phe-
notype associated with mutations in MECP2, a gene
encoding a methyl CpG binding protein. J Med
Genet. 2001;38(4):224–8.
11. Hitchins MP, Rickard S, Dhalla F, Fairbrother UL,
de Vries BB, Winter R, Pembrey ME, Malcolm S.
Investigation of UBE3A and MECP2 in Angelman
syndrome (AS) and patients with features of AS.
Am J Med Genet A. 2004;125A(2):167–72.
Аналіз генетичних та епігенетичних мутацій
гена SNRPN у пацієнтів з синдромами Прадера-
Віллі та Ангельмана
С. Ю. Чернушин, Н. В. Грищенко
Синдроми Прадера-Віллі (СПВ) та Ангельмана (СА) —
це різні за клінічними ознаками генетичні захворю-
вання, які супроводжуються фізичними та когнітив-
ними розладами. Генетичною причиною СПВ та СА
є пошкодження в хромосомній ділянці 15q11.2-q13,
експресія генів якої підлягає геномному імпринтингу.
366
S. Yu. Chernushyn, N. V. Hryshchenko
Мета. Оцінка частоти геномних перебудов та епігене-
тичних порушень в 15q11.2-q13 у групі пацієнтів з
України, які мали фенотипові прояви СПВ та СА.
Методи. Для одночасної детекції як генетичних, так і
епігенетичних порушень, які призводять до СПВ та
СА, аналізувався статус метилування гена SNRPN з
використанням метил-специфічної ПЛР (МС-ПЛР).
Результати. Порушення, яке призводить до СПВ —
відсутність неметильованого гена SNRPN — було
виявлено у 25 (42 %) хворих з фенотипом СПВ. В
групі з СА частота мутацій SNRPN (відсутність гіпо-
метильваного гена) виявлена у 28 % хворих. В групі з
СПВ відмічено достовірне переважання пацієнтів
чоловічої статі. Проте частка жінок з підтвердженим
діагнозом в цій групі була вищою — 56 % проти 36 %.
Менший за очікуваний відсоток підтвердження СПВ
та СА може бути наслідком як помилок клінічної діа-
гностики, так і методичних обмежень. Висновки.
Аналіз ділянки гена SRNPN з використанням МС-ПЛР
може бути запропонований для молекулярної діагнос-
тики СПВ та СА. Прогнозується, що використання
цього методу тестування дозволяє виключити діагноз
СПВ у приблизно 60 % хворих з клінічними ознаками
цього синдрому, у 30 % пацієнтів з ознаками СА —
підтвердити захворювання.
К л юч ов і с л ов а: синдром Прадера-Віллі, синдром
Ангельмана, ген SRNPN, метил-специфічна ПЛР.
Анализ генетических и эпигенетических
мутаций гена SNRPN у пациентов
с синдромами Прадера-Вилли и Ангельмана
С. Ю. Чернушин, Н. В. Грищенко
Синдромы Прадера-Вилли (СПВ) и Ангельмана
(СА) — это разные по клиническим признакам гене-
тические заболевания, которые сопровождаются фи-
зическими и когнитивными расстройствами.
Генетической причиной СПВ и СА является поврежде-
ние в хромосомной области 15q11.2-q13, экспрессия
генов которой подлежит геномному импринтинуг.
Цель. Оценка частоты геномных перестроек и эпиге-
нетических нарушений в 15q11.2-q13 в группе паци-
ентов с Украины с фенотипическими проявлениями
СПВ и СА. Методы. Для одновременной детекций как
генетических, так и эпигенетических нарушений, ко-
торые приводят к СПВ и СА, анализировался статус
метилирования гена SNRPN с использованием ме-
тил-специфической ПЦР (МС-ПЦР). Результаты.
Нарушение, которое приводит к СПВ — отсутствие
неметильованого гена SNRPN — было обнаружено у
25 (42 %) больных с фенотипом СПВ. В группе с СА
частота мутаций SNRPN (отсутствие гипометильвано-
го гена) выявлено у 28 % больных. В группе с СПВ
отмечено достоверное преобладание пациентов муж-
ского пола. Однако доля женщин с подтвержденным
диагнозом в этой группе была выше — 56 % против
36 %. Меньший ожидаемого процент подтверждения
СПВ и СА может быть следствием как ошибок клини-
ческой диагностики, так и методических ограничений.
Выводы. Анализ участка гена SRNPN с использовани-
ем МС-ПЦР может біль предложен для молекулярной
диагностики СПВ и СА. Прогнозируется, что исполь-
зование этого метода тестирования позволяет исклю-
чить диагноз СПВ у примерно 60 % больных с клини-
ческими признаками этого синдрома, у 30 % пациентов
с признаками СА — подтвердить заболевания.
К л юч е в ы е с л ов а: синдром Прадера-Вилли,
синдром Ангельмана, ген SRNPN, метил-специфиче-
ская ПЦР.
Received 01.08.2018
OLE_LINK30
OLE_LINK31
OLE_LINK1
OLE_LINK2
OLE_LINK34
OLE_LINK35
OLE_LINK28
OLE_LINK29
OLE_LINK52
OLE_LINK53
OLE_LINK16
OLE_LINK17
OLE_LINK18
OLE_LINK11
OLE_LINK12
OLE_LINK13
OLE_LINK8
OLE_LINK9
OLE_LINK10
OLE_LINK4
OLE_LINK5
OLE_LINK6
OLE_LINK7
OLE_LINK19
OLE_LINK20
OLE_LINK21
_GoBack
|