PLA2G6 mutations associated with a continuous clinical spectrum from neuroaxonal dystrophy to hereditary spastic paraplegia.

PLA2G6-associated neurodegeneration (PLAN) and hereditary spastic paraplegia (HSP) are 2 groups of heterogeneous neurodegenerative diseases. In this study, we report PLA2G6 gene mutations in 3 families from Turkey, Morocco, and Romania. Two affected Turkish siblings presenting HSP adds the disease to PLAN phenotypes. They were homozygous for the PLA2G6 missense c.2239C>T, p.Arg747Trp variant and the ages of onset were 9 and 21. Parkinsonism, dystonia or cognitive decline were not the clinical elements in these patients contrary to the cases that has been previously reported with the same variant, however, iron accumulation was evident in their cranial magnetic resonance imaging. The Moroccan patient was homozygous for a novel missense c.1786C>T, p.Leu596Phe variant and the Romanian patient had 2 novel mutations; c.1898C>T, p.Ala633Val and c.1765_1768del, p.Ser589ThrfsTer76. Both of these patients conformed better to childhood onset PLAN with the age of onset at 4 and 7 years, respectively. Interestingly, all identified mutations were affecting the highly conserved patatin-like phospholipase domain of the PLA2G6 protein.

Management of pregnancy and obstetric complications in prehospital trauma care: faculty of prehospital care consensus guidelines.

This consensus statement seeks to provide clear guidance for the management of pregnant trauma patients in the prehospital setting. Pregnant patients sustaining trauma injuries have certain clinical management priorities beyond that of the non-pregnant trauma patients and that if overlooked may be detrimental to maternal and fetal outcomes.

Warfarin maintenance dose associated with genetic polymorphisms of CYP2C9.

BACKGROUND: Cytochrome P450 2C9 (CYP2C9) gene polymorphisms alters the required warfarin dose in patients, due to pharmacogenetic events. This study aimed to identify the frequency of the allele CYP2C9 polymorphic variants *2 and *3, and the association of these allelic variants with warfarin dosage in the population of the west Azerbaijan province in Iran. METHODS: One hundred and seventy patients receiving warfarin were examined to evaluate the genotype frequency of common CYP2C9 polymorphisms. Genotype analysis for CYP2C9*2 and CYP2C9*3 polymorphisms was performed by polymerase chain reaction-restriction fragment length polymorphism (PCR-RFLP) assay. To assess if the dosage is different between genotypes we used one-way analysis of variance (ANOVA). RESULTS: Frequency of the two variants in studied subjects was 12 % for CYP2C9*2 and 25.8 % for CYP2C9*3. Comparison of the warfarin daily maintenance dose between genotype groups showed that the daily mean dose of warfarin in patients who have homozygous wild-type genotype for CYP2C9 (*1/*1) was 5.26 ± 2.32 mg, which was significantly higher compared to *1/*2, *1/*3 (3.57 ± 2.25 mg, p <0.001) and *2/*2, *2/*3 and *3/*3 patients (3.76 ± 2.4 mg, p =0.024). Further analysis revealed that the allelic frequency of CYP2C9 polymorphisms in the study population was similar to that of the Turkish population. CONCLUSIONS: Due to the relatively high frequency of CYP2C9 polymorphisms in the study population, the clinicians should become aware of these results to reduce the risk of hemorrhage when prescribing warfarin. HIPPOKRATIA 2017, 21(2): 93-96.

High frequency of GJA12/GJC2 mutations in Turkish patients with Pelizaeus-Merzbacher disease.

Pelizaeus-Merzbacher disease is an early onset dysmyelinating leukodystrophy. About 80% of PMD cases have been associated with duplications and mutations of the proteolipid protein 1 (PLP1) gene. Pelizaeus-Merzbacher-like disease is a genetically heterogeneous autosomal recessive disease and rarely caused by mutations in gap junction protein α12 (GJA12/GJC2) gene. The molecular basis of the disease was investigated in a cohort of 19 Turkish families. This study identified novel chromosomal rearrangements proximal and distal to, and exclusive of the PLP1 gene, showed equal frequencies of PLP1 and GJA12/GJC2 mutations at least in our cohort, and suggested further genetic heterogeneity.

A novel missense mutation in human TTF-2 (FKHL15) gene associated with congenital hypothyroidism but not athyreosis.

BACKGROUND: Thyroid dysgenesis is the most frequent cause of congenital hypothyroidism (CH), and its genetic basis is largely unknown. Hitherto, two mutations in the human thyroid transcription factor 2 (TTF-2) gene have been described in unrelated cases of CH with cleft palate, spiky hair, variable choanal atresia, and complete thyroid agenesis. Here, we describe a novel TTF-2 mutation in a female child resulting in syndromic CH in the absence of thyroid agenesis. RESULTS: The index case is homozygous for an arginine to cysteine mutation (R102C) of a highly conserved residue within the forkhead, DNA binding domain of TTF-2. Her consanguineous, heterozygous parents are unaffected, and the mutation was not detected in 100 control chromosomes. Consonant with its location, the R102C mutant TTF-2 protein showed loss of DNA binding and was transcriptionally inactive. CH in the proposita was associated with cleft palate, spiky hair, and bilateral choanal atresia. However, radiological studies showed the presence of thyroid tissue in a eutopic location. CONCLUSION: Our findings indicate that human thyroid development can occur despite loss of TTF-2 function and suggest that TTF-2 gene defects should also be considered in cases of syndromic CH without total athyreosis.

Absence of KIF1B mutation in a large Turkish CMT2A family suggests involvement of a second gene.

BACKGROUND: Charcot-Marie-Tooth disease type 2A (CMT2A) was assigned to a 19.3-cM region on chromosome 1p35-36. A missense mutation in the kinesin family member 1B gene (KIF1B) was reported in a single CMT2A family. OBJECTIVE: To report the clinical and genetic data of a Turkish family with CMT2A. METHODS: Linkage to CMT2 loci was investigated in the family. Haplotype analysis of the CMT2A region was completed using additional single-nucleotide polymorphism and short tandem repeat markers. The KIF1B gene was sequenced on genomic DNA and cDNA in two patients. RESULTS: A recombination event narrowed the CMT2A locus to a 9.3-cM region flanked by D1S160 and D1S434. No mutation in KIF1B was found. CONCLUSION: The exclusion of KIF1B gene mutations in this family suggests the involvement of another CMT2A gene in the linked region.

Mutational analysis and genotype/phenotype correlation in Turkish Charcot-Marie-Tooth Type 1 and HNPP patients.

The major Charcot- Marie-Tooth Type 1 (CMT1) locus, CMT1A, and Hereditary neuropathy with liability to pressure palsies (HNPP) cosegregate with a 1.5-Mb duplication and a 1.5-Mb deletion, respectively, in band 17p11.2. Point mutations in peripheral myelin gene 22 (PMP22), myelin protein zero (MPZ), and connexin 32 (Cx32) have been reported in CMT1, and in PMP22 in HNPP patients without deletion. We have screened 54 CMT1 patients, of variable clinical severity, and 25 HNPP patients from Turkey, with no duplication or deletion, for mutations in the PMP22 and Cx32 genes. A novel frameshift mutation affecting the second extracellular domain of PMP22 was found in an HNPP patient, while a point mutation in the second transmembrane domain of the protein was detected in a CMT1 patient. Two point mutations affecting different domains of Cx32 were identified in two CMTX patients. Another patient was found to carry a polymorphism in a non-conserved codon of the Cx32 gene. The clinical phenotypes of the patients correlate well with the effect of the mutation on the protein.

Deletion pattern in the dystrophin gene in Turks and a comparison with Europeans and Indians.

Patterns of dystrophin gene deletions in DMD/BMD patients were compared in four populations: Turks (n = 146 deletions), Europeans (n = 838), North Indians (n = 89), and Indians from all over India (n = 103). Statistical tests revealed that there are differences in the proportions of small deletions. In contrast, the distribution of deletion breakpoints and the frequencies of specific deletions commonly observed in the four populations are not significantly different. The variations strongly suggest that sequence differences exist in the introns, and the differences are in agreement with genetic distances among populations. The similarities suggest that some intronic sequences have been conserved and that those will trigger recurrent deletions, since it is unlikely that gene flow would disperse the deleted chromosomes, which vanish from the gene pool in a few generations.

DNA analysis in Turkish Duchenne/Becker muscular dystrophy families.

The molecular genetics of Duchenne/Becker muscular dystrophy was investigated in 81 affected Turkish families. Deletions were detected by multiplex polymerase chain reaction assays and cDNA Southern analyses. The distribution of the deletions along the gene and their correlation to clinical phenotype were different from the studies reported on other populations. Moreover, DNA polymorphisms in mothers were determined using 8 DNA probes and three CA repeat sequences, and a high degree of informativeness was observed.

Carrier detection by DNA analysis in Duchenne muscular dystrophy families.

We applied DNA analysis techniques to Turkish families whose members were afflicted with Duchenne/Becker muscular dystrophy. The aim of this study was to establish a prenatal diagnosis of this anomaly and to determine the carrier state. All of the techniques used in established diagnosis centers are now applied routinely in our laboratory. Both Southern analysis and polymerase chain reaction (PCR) methods were used for deletion detection in patients and restriction enzyme fragment length polymorphism (RFLP) determination for linkage analysis in women at risk. CA repeated sequence length polymorphism, the most recent technique for linkage analysis, was also applied. About 250 individuals from seventy-nine families were investigated and thirty-six entire families were screened. Twenty-five women were found to be carriers while thirty seven were non-carriers. The carrier state could not be determined in three women.