The high-quality genome of Brassica napus cultivar 'ZS11' reveals the introgression history in semi-winter morphotype

Allotetraploid oilseed rape (Brassica napus L.) is an agriculturally important crop. Cultivation and breeding of B. napus by humans has resulted in numerous genetically diverse morphotypes with optimized agronomic traits and ecophysiological adaptation. To further understand the genetic basis of diversification and adaptation, we report a draft genome of an Asian semi-winter oilseed rape cultivar 'ZS11' and its comprehensive genomic comparison with the genomes of the winter-type cultivar 'Darmor-bzh' as well as two progenitors. The integrated BAC-to-BAC and whole-genome shotgun sequencing strategies were effective in the assembly of repetitive regions (especially young long terminal repeats) and resulted in a high-quality genome assembly of B. napus 'ZS11'. Within a short evolutionary period (~6700 years ago), semi-winter-type 'ZS11' and the winter-type 'Darmor-bzh' maintained highly genomic collinearity. Even so, certain genetic differences were also detected in two morphotypes. Relative to 'Darmor-bzh', both two subgenomes of 'ZS11' are closely related to its progenitors, and the 'ZS11' genome harbored several specific segmental homoeologous exchanges (HEs). Furthermore, the semi-winter-type 'ZS11' underwent potential genomic introgressions with B. rapa (A_r ). Some of these genetic differences were associated with key agronomic traits. A key gene of A03.FLC3 regulating vernalization-responsive flowering time in 'ZS11' was first experienced HE, and then underwent genomic introgression event with A_r , which potentially has led to genetic differences in controlling vernalization in the semi-winter types. Our observations improved our understanding of the genetic diversity of different B. napus morphotypes and the cultivation history of semi-winter oilseed rape in Asia.

Integrative RNA- and miRNA-Profile Analysis Reveals a Likely Role of BR and Auxin Signaling in Branch Angle Regulation of B. napus

Oilseed rape (Brassica napus L.) is the second largest oilseed crop worldwide and one of the most important oil crops in China. As a component of plant architecture, branch angle plays an important role in yield performance, especially under high-density planting conditions. However, the mechanisms underlying the regulation of branch angle are still largely not understood. Two oilseed rape lines with significantly different branch angles were used to conduct RNA- and miRNA-profiling at two developmental stages, identifying differential expression of a large number of genes involved in auxin- and brassinosteroid (BR)-related pathways. Many auxin response genes, including AUX1, IAA, GH3, and ARF, were enriched in the compact line. However, a number of genes involved in BR signaling transduction and biosynthesis were down-regulated. Differentially expressed miRNAs included those involved in auxin signaling transduction. Expression patterns of most target genes were fine-tuned by related miRNAs, such as miR156, miR172, and miR319. Some miRNAs were found to be differentially expressed at both developmental stages, including three miR827 members. Our results provide insight that auxin- and BR-signaling may play a pivotal role in branch angle regulation.

Aggravated nausea and vomiting induced by fat emulsion for hyperemesis gravidarum: A case report

WHAT IS KNOWN AND OBJECTIVE

Total parental nutrition (TPN) for hyperemesis gravidarum (HG) is generally effective and well-tolerated. We report a case of aggravated nausea and vomiting caused by fat emulsion.

CASE DESCRIPTION

A 40-year-old pregnant woman through IVF was admitted to the hospital at 11-week gestation and diagnosed with HG. During TPN treatment, the patient suffered from aggravated nausea and vomiting. We identified fat emulsion as the most likely culprit using challenge, dechallenge and rechallenge.

WHAT IS NEW AND CONCLUSION

This is the first report of fat emulsion aggravating nausea and vomiting in such situation.

Discrete breathers in a mass-in-mass chain with Hertzian local resonators

We report on the existence of discrete breathers in a one-dimensional, mass-in-mass chain with linear intersite coupling and nonlinear, precompressed Hertzian local resonators, which is motivated by recent studies of the dynamics of microspheres adhered to elastic substrates. After predicting theoretically the existence of discrete breathers in the continuum and anticontinuum limits of intersite coupling, we use numerical continuation to compute a family of breathers interpolating between the two regimes in a finite chain, where the displacement profiles of the breathers are localized around one lattice site. We then analyze the frequency-amplitude dependence of the breathers by performing numerical continuation on a linear eigenmode (vanishing amplitude) solution of the system near the upper band gap edge. Finally, we use direct numerical integration of the equations of motion to demonstrate the formation and evolution of the identified localized modes in energy-conserving and dissipative scenarios, including within settings that may be relevant to future experimental studies.

Identification of BnaYUCCA6 as a candidate gene for branch angle in Brassica napus by QTL-seq

Oilseed rape (Brassica napus L.) is one of the most important oil crops in China as well as worldwide. Branch angle as a plant architecture component trait plays an important role for high density planting and yield performance. In this study, bulked segregant analysis (BSA) combined with next generation sequencing technology was used to fine map QTL for branch angle. A major QTL, designated as branch angle 1 (ba1) was identified on A06 and further validated by Indel marker-based classical QTL mapping in an F₂ population. Eighty-two genes were identified in the ba1 region. Among these genes, BnaA0639380D is a homolog of AtYUCCA6. Sequence comparison of BnaA0639380D from small- and big-branch angle oilseed rape lines identified six SNPs and four amino acid variation in the promoter and coding region, respectively. The expression level of BnaA0639380D is significantly higher in the small branch angle line Purler than in the big branch angle line Huyou19, suggesting that the genomic mutations may result in reduced activity of BnaA0639380D in Huyou19. Phytohormone determination showed that the IAA content in Purler was also obviously increased. Taken together, our results suggested BnaA0639380D is a possible candidate gene for branch angle in oilseed rape.

Genomic identification, characterization and differential expression analysis of SBP-box gene family in Brassica napus

BACKGROUND

SBP-box genes belong to one of the largest families of transcription factors. Though members of this family have been characterized to be important regulators of diverse biological processes, information of SBP-box genes in the third most important oilseed crop Brassica napus is largely undefined.

RESULTS

In the present study, by whole genome bioinformatics analysis and transcriptional profiling, 58 putative members of SBP-box gene family in oilseed rape (Brassica napus L.) were identified and their expression pattern in different tissues as well as possible interaction with miRNAs were analyzed. In addition, B. napus lines with contrasting branch angle were used for investigating the involvement of SBP-box genes in plant architecture regulation. Detailed gene information, including genomic organization, structural feature, conserved domain and phylogenetic relationship of the genes were systematically characterized. By phylogenetic analysis, BnaSBP proteins were classified into eight distinct groups representing the clear orthologous relationships to their family members in Arabidopsis and rice. Expression analysis in twelve tissues including vegetative and reproductive organs showed different expression patterns among the SBP-box genes and a number of the genes exhibit tissue specific expression, indicating their diverse functions involved in the developmental process. Forty-four SBP-box genes were ascertained to contain the putative miR156 binding site, with 30 and 14 of the genes targeted by miR156 at the coding and 3'UTR region, respectively. Relative expression level of miR156 is varied across tissues. Different expression pattern of some BnaSBP genes and the negative correlation of transcription levels between miR156 and its target BnaSBP gene were observed in lines with different branch angle.

CONCLUSIONS

Taken together, this study represents the first systematic analysis of the SBP-box gene family in Brassica napus. The data presented here provides base foundation for understanding the crucial roles of BnaSBP genes in plant development and other biological processes.

Characterizing Variation of Branch Angle and Genome-Wide Association Mapping in Rapeseed (Brassica napus L.)

Changes in the rapeseed branch angle alter plant architecture, allowing more efficient light capture as planting density increases. In this study, a natural population of rapeseed was grown in three environments and evaluated for branch angle trait to characterize their phenotypic patterns and genotype with a 60K Brassica Infinium SNP array. Significant phenotypic variation was observed from 20 to 70°. As a result, 25 significant quantitative trait loci (QTL) associated with branch angle were identified on chromosomes A2, A3, A7, C3, C5, and C7 by the MLM model in TASSEL 4.0. Orthologs of the functional candidate genes involved in branch angle were identified. Among the key QTL, the peak SNPs were close to the key orthologous genes BnaA.Lazy1 and BnaC.Lazy1 on A3 and C3 homologous genome blocks. With the exception of Lazy (LA) orthologous genes, SQUMOSA PROMOTER BINDING PROTEIN LIKE 14 (SPL14) and an auxin-responsive GRETCHEN HAGEN 3 (GH3) genes from Arabidopsis thaliana were identified close to two clusters of SNPs on the A7 and C7 chromosomes. These findings on multiple novel loci and candidate genes of branch angle will be useful for further understanding and genetic improvement of plant architecture in rapeseed.

Down-regulation of crambe fatty acid desaturase and elongase in Arabidopsis and crambe resulted in significantly increased oleic acid content in seed oil

High oleic oil is an important industrial feedstock that has been one of the main targets for oil improvement in a number of oil crops. Crambe (Crambe abyssinica) is a dedicated oilseed crop, suitable for industrial oil production. In this study, we down-regulated the crambe fatty acid desaturase (FAD) and fatty acid elongase (FAE) genes for creating high oleic seed oil. We first cloned the crambe CaFAD2, CaFAD3 and CaFAE1 genes. Multiple copies of each of these genes were isolated, and the highly homologous sequences were used to make RNAi constructs. These constructs were first tested in Arabidopsis, which led to the elevated oleic or linoleic levels depending on the genes targeted, indicating that the RNAi constructs were effective in regulating the expression of the target genes in nonidentical but closely related species. Furthermore, down-regulation of CaFAD2 and CaFAE1 in crambe with the FAD2-FAE1 RNAi vector resulted in even more significant increase in oleic acid level in the seed oil with up to 80% compared to 13% for wild type. The high oleic trait has been stable in subsequent five generations and the GM line grew normally in greenhouse. This work has demonstrated the great potential of producing high oleic oil in crambe, thus contributing to its development into an oil crop platform for industrial oil production.

Multigenic Control of Pod Shattering Resistance in Chinese Rapeseed Germplasm Revealed by Genome-Wide Association and Linkage Analyses

The majority of rapeseed cultivars shatter seeds upon maturity especially under hot-dry and windy conditions, reducing yield and gross margin return to growers. Here, we identified quantitative trait loci (QTL) for resistance to pod shatter in an unstructured diverse panel of 143 rapeseed accessions, and two structured populations derived from bi-parental doubled haploid (DH) and inter-mated (IF2) crosses derived from R1 (resistant to pod shattering) and R2 (prone to pod shattering) accessions. Genome-wide association analysis identified six significant QTL for resistance to pod shatter located on chromosomes A01, A06, A07, A09, C02, and C05. Two of the QTL, qSRI.A09 delimited with the SNP marker Bn-A09-p30171993 (A09) and qSRI.A06 delimited with the SNP marker Bn-A06-p115948 (A06) could be repeatedly detected across environments in a diversity panel, DH and IF2 populations, suggesting that at least two loci on chromosomes A06 and A09 were the main contributors to pod shatter resistance in Chinese germplasm. Significant SNP markers identified in this study especially those that appeared repeatedly across environments provide a cost-effective and an efficient method for introgression and pyramiding of favorable alleles for pod shatter resistance via marker-assisted selection in rapeseed improvement programs.

Focal dysplasia of the cerebral cortex and infantile spasms associated with somatic 1q21.1-q44 duplication including the AKT3 gene

Somatic and germline duplications or activating mutations of AKT3 have been reported in patients with hemimegalencephaly and megalencephaly. We performed array comparative genomic hybridization on brain tissue and blood in 16 consecutive patients with symptomatic epilepsy due to focal or multilobar malformations of cortical development who underwent surgical treatment of epilepsy. One patient with infantile spasms and a dysplastic left frontal lobe harboured a somatic trisomy of the 1q21.1-q44 chromosomal region, encompassing the AKT3 gene, in the dysplastic brain tissue but not in blood and saliva. Histopathology revealed severe cortical dyslamination, a thin cortex in the premotor area with microgyri and microsulci, immature neurons with disoriented dendrites and areas of cortical heterotopia in the sub-cortical white matter. These cytoarchitectural changes are close to those defining type Ib focal cortical dysplasia. Immunohistochemistry in brain specimens showed hyperactivation of the PI3K/AKT/mTOR pathway. These findings indicate that AKT3 upregulation may cause focal malformations of cortical development. There appears to be an etiologic continuum between hemimegalencephaly and focal cortical dysplastic lesions. The extent of brain malformations due to AKT3 upregulation may be related to the embryonic stage when the post-zygotic gene alteration occurs.

Deep RNA-Seq to unlock the gene bank of floral development in Sinapis arvensis

Sinapis arvensis is a weed with strong biological activity. Despite being a problematic annual weed that contaminates agricultural crop yield, it is a valuable alien germplasm resource. It can be utilized for broadening the genetic background of Brassica crops with desirable agricultural traits like resistance to blackleg (Leptosphaeria maculans), stem rot (Sclerotinia sclerotium) and pod shatter (caused by FRUITFULL gene). However, few genetic studies of S. arvensis were reported because of the lack of genomic resources. In the present study, we performed de novo transcriptome sequencing to produce a comprehensive dataset for S. arvensis for the first time. We used Illumina paired-end sequencing technology to sequence the S. arvensis flower transcriptome and generated 40,981,443 reads that were assembled into 131,278 transcripts. We de novo assembled 96,562 high quality unigenes with an average length of 832 bp. A total of 33,662 full-length ORF complete sequences were identified, and 41,415 unigenes were mapped onto 128 pathways using the KEGG Pathway database. The annotated unigenes were compared against Brassica rapa, B. oleracea, B. napus and Arabidopsis thaliana. Among these unigenes, 76,324 were identified as putative homologs of annotated sequences in the public protein databases, of which 1194 were associated with plant hormone signal transduction and 113 were related to gibberellin homeostasis/signaling. Unigenes that did not match any of those sequence datasets were considered to be unique to S. arvensis. Furthermore, 21,321 simple sequence repeats were found. Our study will enhance the currently available resources for Brassicaceae and will provide a platform for future genomic studies for genetic improvement of Brassica crops.

Bilateral cavitations of ganglionic eminence: a fetal MR imaging sign of halted brain development

SUMMARY

Ganglionic eminence is the main transitory proliferative structure of the ventral telencephalon in human fetal brain and it contributes for at least 35% to the population of cortical interneurons; however data on the human GE anomalies are scarce. We report 5 fetal MR imaging observations with bilateral symmetric cavitations in their GE regions resembling an inverted open C shape and separating the GE itself form the deeper parenchyma. Imaging, neuropathology, and follow-up features suggested a malformative origin. All cases had in common characteristics of lissencephaly with agenesis or severe hypoplasia of corpus callosum of probable different genetic basis. From our preliminary observation, it seems that GE cavitations are part of conditions which are also accompanied by severe cerebral structure derangement.

FLNA genomic rearrangements cause periventricular nodular heterotopia

OBJECTIVE

To identify copy number variant (CNV) causes of periventricular nodular heterotopia (PNH) in patients for whom FLNA sequencing is negative.

METHODS

Screening of 35 patients from 33 pedigrees on an Affymetrix 6.0 microarray led to the identification of one individual bearing a CNV that disrupted FLNA. FLNA-disrupting CNVs were also isolated in 2 other individuals by multiplex ligation probe amplification. These 3 cases were further characterized by high-resolution oligo array comparative genomic hybridization (CGH), and the precise junctional breakpoints of the rearrangements were identified by PCR amplification and sequencing.

RESULTS

We report 3 cases of PNH caused by nonrecurrent genomic rearrangements that disrupt one copy of FLNA. The first individual carried a 113-kb deletion that removes all but the first exon of FLNA. A second patient harbored a complex rearrangement including a deletion of the 3' end of FLNA accompanied by a partial duplication event. A third patient bore a 39-kb deletion encompassing all of FLNA and the neighboring gene EMD. High-resolution oligo array CGH of the FLNA locus suggests distinct molecular mechanisms for each of these rearrangements, and implicates nearby low copy repeats in their pathogenesis.

CONCLUSIONS

These results demonstrate that FLNA is prone to pathogenic rearrangements, and highlight the importance of screening for CNVs in individuals with PNH lacking FLNA point mutations.

Protocadherin 19 mutations in girls with infantile-onset epilepsy

OBJECTIVE

To explore the causative role of PCDH19 gene (Xq22) in female patients with epilepsy.

METHODS

We studied a cohort of 117 female patients with febrile seizures (FS) and a wide spectrum of epilepsy phenotypes including focal and generalized forms with either sporadic or familial distribution.

RESULTS

PCDH19 screening showed point mutations in 13 probands (11%). Mean age at seizure onset was 8.5 months; 8 patients (62%) presented with FS, 4 (33%) with cluster of focal seizures, and 1 with de novo status epilepticus (SE). Subsequent seizure types included afebrile tonic-clonic, febrile, and afebrile SE, absences, myoclonic, and focal seizures. Seven patients (54%) had a clinical diagnosis consistent with Dravet syndrome (DS); 6 (46%) had focal epilepsy. In most patients, seizures were particularly frequent at onset, manifesting in clusters and becoming less frequent with age. Mental retardation was present in 11 patients, ranging from mild (7; 64%) to moderate (1; 9%) to severe (3; 27%). Five patients (38%) had autistic features in association to mental retardation. Mutations were missense (6), truncating (2), frameshift (3), and splicing (2). Eleven were new mutations. Mutations were inherited in 3 probands (25%): 2 from apparently unaffected fathers and 1 from a mother who had had generalized epilepsy.

CONCLUSIONS

PCDH19 is emerging as a major gene for infantile-onset familial or sporadic epilepsy in female patients with or without mental retardation. In our cohort, epileptic encephalopathy with DS-like features and focal epilepsy of variable severity were the associated phenotypes and were equally represented.

Development of a novel Sinapis arvensis disomic addition line in Brassica napus containing the restorer gene for Nsa CMS and improved resistance to Sclerotinia sclerotiorum and pod shattering

An allo-cytoplasmic male sterile line, which was developed through somatic hybridization between Brassica napus and Sinapis arvensis (thus designated as Nsa CMS line), possesses high potential for hybrid production of rapeseed. In order to select for restorer lines, fertile plants derived from the same somatic hybridization combination were self-pollinated and testcrossed with the parental Nsa CMS line for six generations. A novel disomic alien addition line, B. napus-S. arvensis, has been successfully developed. GISH analysis showed that it contains one pair of chromosomes from S. arvensis and 19 pairs from B. napus, and retains stable and regular mitotic and meiotic processes. The addition line displays very strong restoration ability to Nsa CMS line, high resistance to Sclerotinia sclerotiorum and a low incidence of pod shattering. Because the addition line shares these very important agricultural characters, it is a valuable restorer to Nsa CMS line, and is named NR1 here (Nsa restorer no. 1).

Multiplex ligation-dependent probe amplification detects DCX gene deletions in band heterotopia

BACKGROUND

Subcortical band heterotopia (SBH, or double cortex syndrome) is a neuronal migration disorder consisting of heterotopic bands of gray matter located between the cortex and the ventricular surface, with or without concomitant pachygyria. Most cases show diffuse or anteriorly predominant (A>P) migration abnormality. All familial and 53% to 84% of sporadic cases with diffuse or A>P SBH harbor a mutation of the DCX gene, leaving the genetic causes unexplained, and genetic counseling problematic, in the remaining patients. Our purpose was to verify the extent to which exonic deletions or duplications of the DCX gene would account for sporadic SBH with A>P gradient but normal gene sequencing.

METHODS

We identified 23 patients (22 women, 1 man) with sporadic, diffuse, or anteriorly predominant SBH. After sequencing the DCX gene and finding mutations in 12 (11 women, 1 man), we used multiplex ligation-dependent probe amplification (MLPA) to search for whole-exon deletions or duplications in the 11 remaining women. We used semiquantitative fluorescent multiplex PCR (SQF-PCR) and Southern blot to confirm MLPA findings.

RESULTS

MLPA assay uncovered two deletions encompassing exons 3 to 5, and one involving exon 6, in 3 of 11 women (27%) and raised the percentage of DCX mutations from 52% to 65% in our series. SQF-PCR performed in all three women and Southern blot analysis performed in two confirmed the deletions.

CONCLUSIONS

MLPA uncovers large genomic deletions of the DCX gene in a subset of patients with SBH in whom no mutations are found after gene sequencing. Deletions of DCX are an underascertained cause of SBH.

Periventricular heterotopia: phenotypic heterogeneity and correlation with Filamin A mutations

Periventricular heterotopia (PH) occurs when collections of neurons lay along the lateral ventricles or just beneath. Human Filamin A gene (FLNA) mutations are associated with classical X-linked bilateral periventricular nodular heterotopia (PNH), featuring contiguous heterotopic nodules, mega cisterna magna, cardiovascular malformations and epilepsy. FLNA encodes an F-actin-binding cytoplasmic phosphoprotein and is involved in early brain neurogenesis and neuronal migration. A rare, recessive form of bilateral PNH with microcephaly and severe delay is associated with mutations of the ADP-ribosylation factor guanine nucleotide-exchange factor-2 (ARFGEF2) gene, required for vesicle and membrane trafficking from the trans-Golgi. However, PH is a heterogeneous disorder. We studied clinical and brain MRI of 182 patients with PH and, based on its anatomic distribution and associated birth defects, identified 15 subtypes. Classical bilateral PNH represented the largest group (98 patients: 54%). The 14 additional phenotypes (84 patients: 46%) included PNH with Ehlers-Danlos syndrome (EDS), temporo-occipital PNH with hippocampal malformation and cerebellar hypoplasia, PNH with fronto-perisylvian or temporo-occipital polymicrogyria, posterior PNH with hydrocephalus, PNH with microcephaly, PNH with frontonasal dysplasia, PNH with limb abnormalities, PNH with fragile-X syndrome, PNH with ambiguous genitalia, micronodular PH, unilateral PNH, laminar ribbon-like and linear PH. We performed mutation analysis of FLNA in 120 patients, of whom 72 (60%) had classical bilateral PNH and 48 (40%) other PH phenotypes, and identified 25 mutations in 40 individuals. Sixteen mutations had not been reported previously. Mutations were found in 35 patients with classical bilateral PNH, in three with PNH with EDS and in two with unilateral PNH. Twenty one mutations were nonsense and frame-shift and four missense. The high prevalence of mutations causing protein truncations confirms that loss of function is the major cause of the disorder. FLNA mutations were found in 100% of familial cases with X-linked PNH (10 families: 8 with classical bilateral PNH, 1 with EDS and 1 with unilateral PH) and in 26% of sporadic patients with classical bilateral PNH. Overall, mutations occurred in 49% of individuals with classical bilateral PNH irrespective of their being familial or sporadic. However, the chances of finding a mutation were exceedingly gender biased with 93% of mutations occurring in females and 7% in males. The probability of finding FLNA mutations in other phenotypes was 4% but was limited to the minor variants of PNH with EDS and unilateral PNH. Statistical analysis considering all 42 mutations described so far identifies a hotspot region for PNH in the actin-binding domain (P < 0.05).

Multiple attack study on the available triptans in Italy versus placebo

The aim of the study is to evaluate the efficacy and tolerability of the five triptans that are commercially available in Italy (zolmitriptan 2.5 mg, rizatriptan 10 mg, sumatriptan 100 mg, almotriptan 12.5 mg and eletriptan 40 mg). The study was conducted in single-blind versus placebo and its duration was 18 months. At the Headache Centre of the 'Agostino Gemelli' Hospital in Rome we selected 42 patients, suffering from headache with and without aura (International Headache Society Committee on Headache Classification, 1988 Cephalalgia 8:1-96), whose headache frequency ranged between 1- and 4-monthly crises. For a total of 25 crises, for every five consecutive crises, a different triptan was taken. The end-points of the study were as follows: response at 2 h, 'pain free' at 2 h and 'sustained pain free' (at 24 h). The intra-patient consistency and the tolerability were also evaluated. Thirty patients completed the study and the statistical analysis was only applied to these patients. No substantial difference in terms of the efficacy of the triptans was noted; all triptans were well tolerated. These results suggest the possibility of testing different triptans in the same patient in order to identify the ideal drug for every patient.

Topiramate in migraine prophylaxis: a randomised double-blind versus placebo study

The objectives of this paper are to evaluate the efficacy and tolerability of topiramate, given at the dose of 100 mg/day, in the prophylactic treatment of migraine. The hypothesis that migraine is the result of a condition of neuronal hyperexcitability and the quest for drugs that are able to limit the number of crises justifies the attempt to utilise the new antiepileptic drugs in the prophylaxis of this pathology, which is so important due to its high prevalence and due to the high disability it causes. The study was randomised double-blind versus placebo, lasting 16 weeks, and was preceded by a run-in period of 4 weeks. One hundred and fifteen patients were randomly allocated to treatment with topiramate (TPM) or placebo: 35 patients completed the study in the TPM group and 37 patients in the placebo group. At the end of the double-blind phase of study, in the TPM group, we recorded a significant reduction in the frequency of migraine crises (from 5.26 at baseline to 2.60 in the last 4 weeks), a significant reduction in the quantity of symptomatic drugs taken as compared to the placebo control group (from 6.17+/-1.80 SD to 2.57+/-0.80) and a significant downward trend in the number of days of disability over the 16-week period of therapy. In the TPM group, side effects were transient and well tolerated. TPM has thus proven its efficacy and tolerability in the prophylaxis of migraine.

Germline and mosaic mutations of FLN1 in men with periventricular heterotopia

OBJECTIVE

To describe the phenotypic spectrum and genetics of periventricular nodular heterotopia (PNH) caused by FLN1 mutations in four men.

BACKGROUND

X-linked PNH caused by FLN1 mutations (MIM #300049) implies prenatal or early postnatal lethality in boys and 50% recurrence risk in daughters of affected women.

METHODS

Clinical examination, cognitive testing, MRI, and mutation analysis (denaturing high-performance liquid chromatography and direct sequencing) on blood lymphocytes and single hair roots were performed for nine affected individuals, including three men. Neuropathologic study of the brain was performed for an affected boy.

RESULTS

In two families, missense mutations were transmitted from mother to son (Met102Val) and from father to daughter (Ser149Phe), causing mild phenotypes in both genders, including unilateral PNH. In a third family, a man was mosaic for an A>G substitution (intron 11 acceptor splice site) on leukocyte DNA and hair roots (mutant = 42% and 69%). Single hair root analysis confirmed that the mutation was not present in all ectodermal derivative cells. A healthy daughter had inherited the X chromosome from her father's wild-type germinal cell population. In the fourth family, an eight-base deletion (AGGAGGTG, intron 25 donor splice site) led to early deaths of boys. Postmortem study in a newborn boy revealed PNH and cardiovascular, genitourinary, and gut malformations.

CONCLUSIONS

Periventricular nodular heterotopia caused by FLN1 mutations in men has a wide clinical spectrum and is caused by different genetic mechanisms, including somatic mosaicism. Mutation analysis of FLN1 should support genetic counseling in men with periventricular nodular heterotopia.