FUNCTIONAL CLASSIFICATION OF CHILDREN WITH CEREBRAL PALSY IN KRAPINA-ZAGORJE COUNTY.

The aim was to study functional abilities and to create functional classification of children with cerebral palsy (CP) in Krapina-Zagorje County, based on the classification of gross and fine motor skills and associated impairments. Classification was performed according to the SCPE (Surveillance of Cerebral Palsy in Europe) criteria. We used standardized and complementary functional classification systems for cerebral palsy to create a functional profile. Research included 44 children with CP in the age range of 4 to 18 years. The results showed that the majority of children had bilateral spastic CP (63.6%), followed by unilateral spastic (22.7%) while the representation of dyskinetic CP was 9.09% and ataxic CP 4.55%. Based on the classification of gross and fine motor skills, 43.2% of children had the ability to walk, 11% of children could walk with assistive mobility devices, while 45.4% of children had a low functional level. The study also analyzed the associated impairments where higher classification score of motor impairment correlated with the severity of impairment. The results showed that children with dyskinetic CP and severe motor impairment could have mild cognitive impairment. We systematically present the neuropsychological and functional profile according to the CP type.

Prognostic value of cranial ultrasonography in comparison with magnetic resonance imaging in children with cerebral palsy: a population-based study.

The aim of this population-based study was to evaluate the characteristics of cerebral palsy (CP) in relation to the predominant pattern of the Magnetic Resonance Imaging Classification System (MRICS) that was analogously applied to the neonatal/early infant cranial ultrasound (CUS). The study included children born during the 2004-2007 period from the Croatian part (C28 RCP-HR) of the Surveillance of Cerebral Palsy in Europe (SCPE) CP register. Motor functions, accompanying impairments and brain MRI were evaluated in 227 children, 185 of which also had CUS. Concerning CP types, 56% of children had bilateral spastic, 34% unilateral spastic, 9% dyskinetic and 1% ataxic CP type. Gross Motor Function Classification System (GMFCS) revealed that 62.05% had mild (GMFCS I-III) and 37.85% had severe motor impairment (GMFCS IV-V). CUS showed white matter injury in 60%, gray matter injury in 12%, maldevelopments in 8%, miscellaneous changes in 14%, while 6% were normal; MRI showed significant agreement (κ=0.675, p<0.001). Neuroimaging findings of maldevelopments and predominant gray matter injury were associated with more severe CP, but 7% of children with CP had normal MRI. As we found very good agreement between CUS and MRI findings, CUS is recommended in children at an increased risk of CP if MRI is not available.

Visual impairment in children with cerebral palsy: Croatian population-based study for birth years 2003-2008.

AIM: To evaluate visual impairment (VI) in children with cerebral palsy (CP). METHODS: This population-based study included 419 children from the Surveillance of Cerebral Palsy in Europe (SCPE) C28 RCP-HR - Register of Cerebral Palsy of Croatia born 2003-2008. Vision in children with CP (according to SCPE) was classified as normal or impaired, with the subcategory of severe VI. The proportion of children with VI was assessed in groups with different CP type/subtype, gross and fine motor function, and gestational age (GA). RESULTS: A total of 266 children had some degree of VI (266/400; 66.5%), 134 had normal vision, and data on VI were unknown for 19 children. Severe VI was present in 44 children (44/400; 11%). The proportion of children with VI and severe VI increased with the Gross Motor Function Classification System and Bimanual Fine Motor Function levels. Children with bilateral spastic CP had the highest frequency of severe VI (14.9%). The percentage of severe VI in children with bilateral spastic CP was 53.8% in the group born <28 weeks of GA, 13.3% in the group born 28-31 weeks of GA, 11.1% in the group born 32-36 weeks of GA, and 24.4% in the group born >36 weeks of GA (λ2=4.95; df=6; P<0.001). CONCLUSION: Children with CP have a high prevalence of VI and severe VI, which is increasing with the level of motor impairment. Severe VI is significantly more common in children with bilateral spastic CP, especially among extremely premature infants.

Epilepsy in patients with pineal gland cyst.

OBJECTIVE: The aim of the study is to describe types of epileptic seizures in patients with pineal gland cyst (PGC) and their outcome during follow up period (6-10 years). We wanted to determine whether patients with epilepsy differ in PGC volume and compression of the PGC on surrounding brain structures compared to patients with PGC, without epilepsy. PATIENTS AND METHODS: We analyzed prospectivelly 92 patients with PGC detected on magnetic resonance (MR) of the brain due to various neurological symptoms during the period 2006-2010. Data on described compression of the PGC on surrounding brain structures and size of the PGC were collected. RESULTS: 29 patients (16 women, 13 men), mean age 21.17 years had epilepsy and PGC (epilepsy group). 63 patients (44 women, 19 men), mean age 26.97 years had PGC without epilepsy (control group). Complex partial seizures were present in 8 patients, complex partial seizures with secondary generalization in 8 patients, generalized tonic clonic seizures (GTCS) in 10 and absance seizures in 3 patients. Mean PGC volume in epilepsy group was 855.93 mm3, in control group 651.59 mm3. There was no statistically significant difference between epilepsy and control group in PGC volume. Compression of PGC on surrounding brain structures was found in 3/29 patients (10.34%) in epilepsy group and in 11/63 patients (17.46%) in control group with no statistically significant difference between epilepsy and control group. All patients with epilepsy were put on antiepileptic therapy (AET). During the follow up period, 23 patients (79.31%) were seizure free, 3 patients (13.04%) had reduction in seizure frequency, whereas 3 patients had no improvement in seizure frequency. Two patients from epilepsy group and 3 patients from control group were operated with histologically confirmed diagnosis of PGC in 4, and pinealocytoma in 1 patient. CONCLUSIONS: In patients with PGC, epileptic seizures were classified as: complex partial seizures (with or without secondary generalization), GTCS and absance seizures. All patients were put on AET. During follow up period 79.31% patients were seizure free. There was no difference in PGC volume, nor in described compression of the PGC on surrounding brain structures between epilepsy and control group. Based on our findings, pathomechanism of epileptic seizures in patients with PGC cannot be attributable solely to PGC volume or described compression on surrounding brain structures based on MRI findings.

The characteristics of transcranial color-coded duplex sonography in children with cerebral arteriovenous malformation presenting with headache.

PURPOSE: Cerebral arteriovenous malformations (AVM) are uncommon lesions. They are most often presented in childhood as intracranial hemorrhage. The aim of this report is to present the use of transcranial color-coded duplex sonography (TCCS) in detection of AVMs in children suffering headache. METHODS: This report describes five pediatric patients with headache and cerebral AVM which were initially discovered by TCCS. Diagnosis was confirmed by magnetic resonance imaging and digital subtraction angiography. RESULTS: In all patients, TCCS showed saccular enlargement of the vessels with a multicolored pattern corresponding to the different directions of blood flow. Spectral analysis showed significantly high flow systolic and diastolic velocities and low resistance index. CONCLUSIONS: In this report, we describe TCCS as a valuable non-invasive, harmless, low-cost, widely available method for the detection and follow-up of hemodynamic changes of AVMs in children with headache, before and after treatment.

MRI classification system (MRICS) for children with cerebral palsy: development, reliability, and recommendations.

AIM: To develop and evaluate a classification system for magnetic resonance imaging (MRI) findings of children with cerebral palsy (CP) that can be used in CP registers. METHOD: The classification system was based on pathogenic patterns occurring in different periods of brain development. The MRI classification system (MRICS) consists of five main groups: maldevelopments, predominant white matter injury, predominant grey matter injury, miscellaneous, and normal findings. A detailed manual for the descriptions of these patterns was developed, including test cases (www.scpenetwork.eu/en/my-scpe/rtm/neuroimaging/cp-neuroimaging/). A literature review was performed and MRICS was compared with other classification systems. An exercise was carried out to check applicability and interrater reliability. Professionals working with children with CP or in CP registers were invited to participate in the exercise and chose to classify either 18 MRIs or MRI reports of children with CP. RESULTS: Classification systems in the literature were compatible with MRICS and harmonization possible. Interrater reliability was found to be good overall (k=0.69; 0.54-0.82) among the 41 participants and very good (k=0.81; 0.74-0.92) using the classification based on imaging reports. INTERPRETATION: Surveillance of Cerebral Palsy in Europe (SCPE) proposes the MRICS as a reliable tool. Together with its manual it is simple to apply for CP registers.

Epilepsy in Rett syndrome--lessons from the Rett networked database.

OBJECTIVE: Rett syndrome is an X-linked dominant neurodevelopmental disorder caused by mutations in the MECP2 gene, and characterized by cognitive and communicative regression, loss of hand use, and midline hand stereotypies. Epilepsy is a core symptom, but literature is controversial regarding genotype-phenotype correlation. Analysis of data from a large cohort should overcome this shortcoming. METHODS: Data from the Rett Syndrome Networked Database on 1,248 female patients were included. Data on phenotypic and genotypic parameters, age of onset, severity of epilepsy, and type of seizures were collected. Statistical analysis was done using the IBM SPSS Version 21 software, logistic regression, and Kaplan-Meier survival curves. RESULTS: Epilepsy was present in 68.1% of the patients, with uncontrolled seizures in 32.6% of the patients with epilepsy. Mean age of onset of epilepsy was 4.68 ± (standard deviation) 3.5 years. Younger age of onset was correlated to severity of epilepsy (Spearman correlation r = 0.668, p < 0.01). Patients with late truncating deletions had lower prevalence of epilepsy. Compared to them, the p.R133C mutation, associated with a milder Rett phenotype, increased the risk for epilepsy (odds ratio [OR] 2.46, confidence interval [CI] 95% 1.3-4.66), but not for severe epilepsy. The p.R255X mutation conferred an increased risk for epilepsy (OR 2.07, CI 95% 1.2-3.59) as well as for severe epilepsy (OR 3.4, CI 95% 1.6-7.3). The p.T158M and p.C306C mutations relatively increased the risk for severe epilepsy (OR 3.09 and 2.69, CI 95% 1.48-6.4 and 1.19-6.05, respectively), but not for epilepsy occurrence. SIGNIFICANCE: Various mutations in the MECP2 gene have a different influence on epilepsy, unrelated to the severity of the general Rett phenotype. This might suggest a site-specific effect of MeCp2 on epileptic pathways. Further investigation of these mechanisms should promote better understanding of epileptogenesis in Rett syndrome.

Visual stimulations' critical period in infants with perinatal brain damage.

BACKGROUND: Children with perinatal brain damage have a high prevalence of visual impairment. Stimulation of vision at a critical period can encourage brain plasticity and the recovery of impaired function. OBJECTIVE: The aim of our study was to investigate when is the critical period for visual stimulation in children with perinatal brain damage. METHODS: We compared 35 children within the first eight months of life (median age = 4 months) to 35 children aged between eight and thirty months (median age = 15 months), all with perinatal brain damage. All the children were attending an early intervention program at Mali dom, Zagreb, a rehabilitation centre for children with visual impairment. We compared the results from baseline and follow-up assessments of visual functions (grating acuity and contrast sensitivity). We also compared differences in change scores between the two groups. RESULTS: Our results have shown that children who commence a visual stimulation program within the first eight months of life had more improvement in both visual functions. This improvement is statistically significant in visual acuity (p = 0.048). CONCLUSIONS: These results indicate the importance of starting a visual stimulation program within the first eight months after birth.

Multiple presence of prothrombotic risk factors in Croatian children with arterial ischemic stroke and transient ischemic attack.

AIM: To determine the frequency of inherited and acquired prothrombotic risk factors in children with arterial ischemic stroke (AIS) and transient ischemic attacks (TIA) in Croatia. METHODS: We investigated 14 prothrombotic risk factors using blood samples from 124 children with AIS or TIA and 42 healthy children. Prothrombotic risk factors were classified into five groups: natural coagulation inhibitors (antithrombin, protein C, protein S), blood coagulation factors (FV Leiden and FII 20210), homocysteine, lipid and lipoprotein profile (lipoprotein (a), triglycerides, total, high- and low-density lipoprotein), and antiphospholipid antibodies (lupus anticoagulant, anticardiolipin, and antiphosphatidylserine antibodies). RESULTS: The most common prothrombotic risk factor was elevated lipoprotein (a), which was identified in about 31% of patients and in 24% of controls. Natural coagulation inhibitors were decreased in about 19% of patients, but not in controls. Pathological values of homocysteine, blood coagulation factor polymorphisms, and antiphospholipid antibodies were found in similar frequencies in all groups. Fourteen children with AIS and TIA (11.3%) and no children from the control group had three or more investigated risk factors. CONCLUSION: The presence of multiple prothrombotic risk factors in children with cerebrovascular disorder suggests that a combination of risk factors rather than individual risk factors could contribute to cerebrovascular disorders in children.

The effect of vibration therapy on spasticity and motor function in children with cerebral palsy: a randomized controlled trial.

As the motor system relies heavily on deep sensory stimulation, recent studies have investigated the effect of vibration stimuli. Although research suggests a positive influence of vibration on motor performance in individuals with neurological disorders, there are very limited numbers of studies in children with cerebral palsy (CP). The objective of the present study was to evaluate the effects of sound wave vibration therapy on spasticity and motor function in children with CP. In this 3-month trial, 89 children with spastic CP were randomized to either continue their physiotherapy treatment (PT) or to receive vibration therapy twice a week in addition to their PT program. The randomization was stratified according to the Gross Motor Function Classification System (GMFCS) level to ensure similar functional ability. Children were assessed at baseline and after the 12-week intervention period. The outcomes measured were spasticity level as assessed by Modified Modified Ashworth Scale (MMAS) and gross motor function as assessed by Gross Motor Function Measurement (GMFM-88). Subgroup analysis was performed for the GMFCS. Significant differences between groups were detected for changes in spasticity level and gross motor function after the three months intervention. In conclusion, vibration therapy may decrease spasticity and improve motor performance in children with CP. The results of the present trial serve as valuable input for evidence-based treatments in paediatric neurorehabilitation.

Rett networked database: an integrated clinical and genetic network of Rett syndrome databases.

Rett syndrome (RTT) is a neurodevelopmental disorder with one principal phenotype and several distinct, atypical variants (Zappella, early seizure onset and congenital variants). Mutations in MECP2 are found in most cases of classic RTT but at least two additional genes, CDKL5 and FOXG1, can underlie some (usually variant) cases. There is only limited correlation between genotype and phenotype. The Rett Networked Database (http://www.rettdatabasenetwork.org/) has been established to share clinical and genetic information. Through an "adaptor" process of data harmonization, a set of 293 clinical items and 16 genetic items was generated; 62 clinical and 7 genetic items constitute the core dataset; 23 clinical items contain longitudinal information. The database contains information on 1838 patients from 11 countries (December 2011), with or without mutations in known genes. These numbers can expand indefinitely. Data are entered by a clinician in each center who supervises accuracy. This network was constructed to make available pooled international data for the study of RTT natural history and genotype-phenotype correlation and to indicate the proportion of patients with specific clinical features and mutations. We expect that the network will serve for the recruitment of patients into clinical trials and for developing quality measures to drive up standards of medical management.

Language development in preschool children born after asymmetrical intrauterine growth retardation.

BACKGROUND: After intrauterine growth retardation, many minor neurodevelopmental disorders may occur, especially in the motor skills domain, language and speech development, and cognitive functions. AIM: The assessment of language development and impact of postnatal head growth in preschool children born with asymmetrical intrauterine growth retardation. METHODS: Examinees were born at term with birth weight below the 10th percentile for gestational age, parity and gender. Mean age at the time of study was six years and four months. The control group was matched according to chronological and gestational age, gender and maternal education with mean age six years and five months. There were 50 children with intrauterine growth retardation and 50 controls, 28 girls and 22 boys in each group. For the assessment of language development Reynell Developmental Language Scale, the Naming test and Mottier test were performed. RESULTS: There were statistically significant differences (p < 0.05) in language comprehension, total expressive language (vocabulary, structure, content), naming skills and non-words repetition. Statistically significant positive correlations were found between relative growth of the head [(Actual head circumference - head circumference at birth)/(Body weight - birth weight)] and language outcome. Children with neonatal complications had lower results (p < 0.05) in language comprehension and total expressive language. CONCLUSION: Intrauterine growth retardation has a negative impact on language development which is evident in preschool years. Slow postnatal head growth is correlated with poorer language outcome. Neonatal complications were negatively correlated with language comprehension and total expressive language.

Stimulation of functional vision in children with perinatal brain damage.

Cerebral visual impairment (CVI) is one of the most common causes of bilateral visual loss, which frequently occurs due to perinatal brain injury. Vision in early life has great impact on acquisition of basic comprehensions which are fundamental for further development. Therefore, early detection of visual problems and early intervention is necessary. The aim of the present study is to determine specific visual functioning of children with perinatal brain damage and the influence of visual stimulation on development of functional vision at early age of life. We initially assessed 30 children with perinatal brain damage up to 3 years of age, who were reffered to our pediatric low vision cabinet in "Little house" from child neurologists, ophthalmologists Type and degree of visual impairment was determined according to functional vision assessment of each child. On the bases of those assessments different kind of visual stimulations were carried out with children who have been identified to have a certain visual impairment. Through visual stimulation program some of the children were stimulated with light stimulus, some with different materials under the ultraviolet (UV) light, and some with bright color and high contrast materials. Children were also involved in program of early stimulation of overall sensory motor development. Goals and methods of therapy were determined individually, based on observation of child's possibilities and need. After one year of program, reassessment was done. Results for visual functions and functional vision were compared to evaluate the improvement of the vision development. These results have shown that there was significant improvement in functional vision, especially in visual attention and visual communication.

Effects of vibrotactile stimulation on the control of muscle tone and movement facilitation in children with cerebral injury.

Afferent signals from the muscle's proprioceptors play important role in the control of muscle tone and in the facilitation of movements. Peripheral afferent pathway enables the restoration of connections with supraspinal structures and so includes mechanism of synaptic inhibition in the performance of normal movement. Different sensory stimuli, as vibrotactile stimulation, excite muscle's proprioceptors which then send sensorimotor information via spinal cord. In this way afferent signals promote cortical control and modulation of movements. The goal of this study is to evaluate the effects of vibrotactile stimulation on the spasticity and motor performance in children with cerebral injury. Subjects included in this study were 13 children who were developing the classification of spastic cerebral palsy. For all children perinatal brain damage was documented by medical reports and neonatal brain ultrasound scan. At the mean age of 3 years and 6 months subject underwent the assessment of motor development by Gross Motor Function Measurement (GMFM-88). Gross Motor Classification System (GMFCS) has been used to classify functions of lower extremities. Therapeutic intervention was conducted once a week during 3 months. All subjects were stimulated with vibrotactile stimuli of 40Hz in duration of 20 minutes in order to reduce spasticity. After the ending of the treatment subjects underwent second assessment of motor performance and the classification of lower extremities functions. The results have shown that there was a significant improvement in motor performance, what has been seen in the facilitation of rotations, better postural trunk stability and head control and in greater selectivity of movements. Further randomized, control trial investigations with bigger sample and included spasm scale are needed to gain better insight in the role of vibrotactile stimulation in the facilitation of normal movements.

Lenticulostriatal vasculopathy - a marker for congenital cytomegalovirus infection?

Lenticulostriate vasculopathy (LSV) is an ultrasound (US) visible lesion of the brain, which appears as echogenic streaks or spots in the arteries of thalamus and basal ganglia. LSV has varied etiology. Transfontanelar Color Doppler (TFCD) can easily display lenticulostriatal blood flow and assess: stage I LSV with present flow within echogenic changes and stage II LSV in which the flow disappears, despite a presence of streaks and spots, which at this stage most probably correspond to calcification. The objectives of this study are to determine: (1) Whether there are differences in distribution (unilateral or bilateral) and presence (during first year of age) of TFCD flow between congenital CMV infection positive and negative group of children with LSV (2) Could US and TFCD findings of LSV be an indication for further investigation of possible congenital CMV infection, because of their variable and often adverse neurodevelopmental outcome? We examined and followed-up 98 infants with LSV One group (37/98) with congenital CMV infection and second (61/98) negative. All infants had clinical signs of neuromotor delay and ultrasound and TFCD markers of LSV Our study shows that most of the patients from both groups had TFCD visible flow at the age of 0-4 months. In majority of them in both groups, at the age of 5-8 months, there was no more visible flow. TFCD showed no statistically significant difference among congenital CMV infection positive group and negative group, nor in youngest age period (0-4 months), nor in later course of flow in LSV unilaterally or bilaterally. Although the LSV presents nonspecific marker for intracranial infection (ICI), all infants presenting with LSV should be evaluated for possible ICI. Thus, the Doppler findings of LSV in infants require a detailed examination, monitoring and follow-up of neuromotor outcome.

An overview of L-2-hydroxyglutarate dehydrogenase gene (L2HGDH) variants: a genotype-phenotype study.

L-2-Hydroxyglutaric aciduria (L2HGA) is a rare, neurometabolic disorder with an autosomal recessive mode of inheritance. Affected individuals only have neurological manifestations, including psychomotor retardation, cerebellar ataxia, and more variably macrocephaly, or epilepsy. The diagnosis of L2HGA can be made based on magnetic resonance imaging (MRI), biochemical analysis, and mutational analysis of L2HGDH. About 200 patients with elevated concentrations of 2-hydroxyglutarate (2HG) in the urine were referred for chiral determination of 2HG and L2HGDH mutational analysis. All patients with increased L2HG (n=106; 83 families) were included. Clinical information on 61 patients was obtained via questionnaires. In 82 families the mutations were detected by direct sequence analysis and/or multiplex ligation dependent probe amplification (MLPA), including one case where MLPA was essential to detect the second allele. In another case RT-PCR followed by deep intronic sequencing was needed to detect the mutation. Thirty-five novel mutations as well as 35 reported mutations and 14 nondisease-related variants are reviewed and included in a novel Leiden Open source Variation Database (LOVD) for L2HGDH variants (http://www.LOVD.nl/L2HGDH). Every user can access the database and submit variants/patients. Furthermore, we report on the phenotype, including neurological manifestations and urinary levels of L2HG, and we evaluate the phenotype-genotype relationship.

L-2-Hydroxyglutaric aciduria: pattern of MR imaging abnormalities in 56 patients.

PURPOSE: To describe the pattern of magnetic resonance (MR) imaging abnormalities in l-2-hydroxyglutaric aciduria (L2HGA) and to evaluate the correlation between imaging abnormalities and disease duration. MATERIALS AND METHODS: MR images in 56 patients (30 male, 26 female; mean age +/- standard deviation, 11.9 years +/- 8.5) with genetically confirmed L2HGA were retrospectively reviewed, with institutional review board approval and waiver of informed consent. At least one complete series of transverse T2-weighted images was available for all patients. The images were evaluated by using a previously established scoring list. The correlation between MR imaging abnormalities and disease duration was assessed (Mann-Whitney or Kruskal-Wallis test). RESULTS: The cerebral white matter (WM) abnormalities preferentially affected the frontal and subcortical regions. The abnormal subcortical WM often had a mildly swollen appearance (37 patients). Initially, the WM abnormalities were at least partially multifocal (32 patients). In patients with longer disease duration, the WM abnormalities became more confluent and spread centripetally, but the periventricular rim remained relatively spared (41 patients). The mean disease duration in patients with WM atrophy (14.8 years) was significantly longer (P = .001) than that in patients without atrophy (6.7 years). Bilateral involvement of the globus pallidus (55 patients), caudate nucleus (56 patients), and putamen (56 patients) was seen at all stages. The cerebellar WM was never affected. The dentate nucleus was involved bilaterally in 55 of 56 patients. CONCLUSION: L2HGA has a distinct highly characteristic pattern of MR imaging abnormalities: a combination of predominantly subcortical cerebral WM abnormalities and abnormalities of the dentate nucleus, globus pallidus, putamen, and caudate nucleus. With increasing disease duration, WM abnormalities and basal ganglia signal intensity abnormalities become more diffuse and cerebral WM atrophy ensues.

MKS3/TMEM67 mutations are a major cause of COACH Syndrome, a Joubert Syndrome related disorder with liver involvement.

The acronym COACH defines an autosomal recessive condition of Cerebellar vermis hypo/aplasia, Oligophrenia, congenital Ataxia, Coloboma and Hepatic fibrosis. Patients present the "molar tooth sign", a midbrain-hindbrain malformation pathognomonic for Joubert Syndrome (JS) and Related Disorders (JSRDs). The main feature of COACH is congenital hepatic fibrosis (CHF), resulting from malformation of the embryonic ductal plate. CHF is invariably found also in Meckel syndrome (MS), a lethal ciliopathy already found to be allelic with JSRDs at the CEP290 and RPGRIP1L genes. Recently, mutations in the MKS3 gene (approved symbol TMEM67), causative of about 7% MS cases, have been detected in few Meckel-like and pure JS patients. Analysis of MKS3 in 14 COACH families identified mutations in 8 (57%). Features such as colobomas and nephronophthisis were found only in a subset of mutated cases. These data confirm COACH as a distinct JSRD subgroup with core features of JS plus CHF, which major gene is MKS3, and further strengthen gene-phenotype correlates in JSRDs.

Megalencephalic leukoencephalopathy with subcortical cysts: an update and extended mutation analysis of MLC1.

Megalencephalic leukoencephalopathy with subcortical cysts (MLC) is an autosomal recessive cerebral white matter disorder in children. This disease is histopathologically characterized by myelin splitting and intramyelinic vacuole formation. MLC is caused by mutations in the gene MLC1, which encodes a novel protein, MLC1. Since the first report, 50 mutations in this gene have been found. Mutations occur throughout the entire coding region and include all different types: 11 splice-site mutations; one nonsense mutation; 24 missense mutations; and 14 deletions and insertions. Until now, six polymorphisms within the coding sequence of MLC1 had been reported. In about 20% of the patients with a typical clinical and MRI picture, no mutations in the MLC1 gene are found. Several of the families, in which no mutations are found, also do not show linkage with the MLC1 locus, which suggests a second gene involved in MLC. The absence of mutations may also be the consequence of performing standard mutation analysis that can miss heterozygous deletions, mutations in the promoter, 3' and 5' untranslated regions (UTRs), and intron mutations, which may influence the amino acid composition of the end product. In this work we describe 13 novel mutations, including those found with extended mutation analysis on MLC patients. This study shows that extended mutation analysis is a valuable tool to identify at least some of the missing mutations. Therefore, we suggest extended mutation analysis for the MLC1 gene, if no mutations are found during standard analysis.