High frequency of mutations in the PIK3CA gene helical and kinase coding regions in a group of Iranian patients with high-grade glioblastomas: five novel mutations

Glioblastoma multiform (GBM; World Health Organization (WHO) grade IV) and anaplastic astrocytomas (AA; WHO grade III) are highly aggressive and lethal astrocytic brain tumors. To detect cancer-specific somatic mutations in two hot-spot regions of PIK3CA gene, the helical and kinase domains (encoded by exons 9 and 20, respectively) in GBM and AA, the authors examined the respective sequences 31 paraffin-embedded samples (23 GBM and 8 AA). The samples were obtained from a group of Iranian patients affected with high-grade glioblastoma (HGG). The overall prevalence of PIK3CA mutations was 23% (7/31) for both tumor types (22% in GBM, and 25% in AA). Five mutations were detected in exon 20, p.Arg992Gln (c.2976G→A), p.Met1005Val (c.3014A→G), p.Ile1019→Val (c.3056A→G), p.Ser1008Cys (c.3024C→G), and p.Asn1044Asp (c.3130A→G), and one mutation in exon 9, p.Glu545Ala (c.1634A→C). Additionally exons 4-8 of P53 gene in four unrelated young patients, who showed no mutations in PIK3CA exons 9 and 20, were analyzed. Three mutations were identified: p.Pro72Ala (c.214C→G), g.11608G→T (homozygote splice mutation), and p.Thr170Thr (c.510G→A silent mutation). In conclusion, mutation detection in PIK3CA in patients with a high degree of malignancy and early age at diagnosis should be included in molecular diagnostic protocols, also with regard to possible upcoming therapies.     

Histological assessment of pulp condition after apical vital root transection in one root of multirooted teeth in dogs: a preliminary study

One of the most important aspects in surgery is the healing process after the periapical surgery. Past studies have shown occasional encounters with vital root resection and have noted varying degrees of pulpal response after root resection in periodontal disease. The purpose of this investigation was to observe the pulpal and periapical responses to intentional apical vital root transection in one root of multirooted teeth of German-Canadian dogs over a 6-month postoperative period. This is an experimental study performed on left maxillary and mandibular quadrants of four adult German-Canadian dogs after a 3- and 6-month period. Four teeth were assessed in each interval. One of the roots of multirooted teeth in the left quadrant of both maxillary and mandibular jaws was surgically transected. Tissue blocks were prepared by routine histological methods after 12 and 24 weeks after the surgery. The results showed a disruption of the normal pulpal architecture, with initial pulpal degeneration and subsequent early replacement by the periodontal ligament tissue after 24 weeks. Hypercementosis was seen around the apical portion of the root in all specimens. Pulpal regeneration was seen in the both upper and lower molars (p = 0.03). Resorption took place only in two specimens (p = 0.46). The inflammation in the 12th week was more than the 24th week. The pulp of multirooted teeth remains vital after transection of the apical part of the root in dogs. Longer follow-up periods are recommended because root canal therapy or extraction is indicated if resorption, necrosis, or ankylosis is seen.     

Intraspecific variation within Phlebotomus sergenti Parrot (1917) (Diptera: Psychodidae) based on mtDNA sequences in Islamic Republic of Iran

An intraspecific study on the morphological and molecular characteristics of Phlebotomus sergenti s.l., the main vector of Leishmania tropica, was performed on 28 Iranian populations from 11 provinces and a few samples from Greece, Morocco, Lebanon, Turkey, Pakistan, and Syria. Three morphotypes were identified as A, B and C, with some intermediate forms in the samples under investigation. Based on the number of setae and the width of basal lobe of coxite, differences between A and B morphotypes were highly significant. Excluding one unusual haplotype, sequence analysis of approximately 439 bp of mtDNA (a fragment of cytochrome B gene, tRNA for serine gene, and a fragment of NADH1 gene) revealed a 6-7% genetic distance within the Iranian populations and among the specimens of other countries. Neighbor-Joining (NJ) analysis confirmed the existence of three main groups within our samples. Although there was no consistency between morphotypes and genotypes, but an interrelationship was found between morphometry and morphotypes. Morphotype A, which was considered as P. sergenti sergenti, was the most prevalent in collection sites. Morphotype B, which was identified as Phlebotomus sergenti similis, is the first record of this subspecies in Iran, and was found to be sympatric with other morphotypes. Morphotype C had an elongated style in comparison with P. sergenti sergenti. Molecular database showed three main genetic structures. This is the first combined morphological and molecular studies on P. sergenti s.l. in Iran.     

A comprehensive molecular characterization of beta thalassemia in a highly heterogeneous population

In Iran, the prevalence of beta-thalassemia trait is approximately 4-8% in most areas, and in Mazandaran province 10% of the population are carriers. Twenty four beta-globin gene mutations were identified in 1635 persons with beta-thalassemia trait using reverse dot blot and restriction fragment length polymorphism analysis. The predominant mutations included IVSII-1 (G-A) (61%), codon 30 (G-C) (7.5%), codon 22 (-7bp) (6.2%), codon 8 (-AA) (5.4%) and IVSI-5 (G-C) (3.6%). These mutations were in different haplotypes, with IVSII-1 being the most heterogeneous. Other less frequent mutations included IVS-II-745 (C-G), codon 44 (-C), codon 39 (C-T), codon 5 (-CT), IVS I-110 (G-A), IVSI-130 (G-C), Fr8/9 (+G), IVSI-1 (G-A), and IVSI (-25bp). All rare mutations except IVSI-130 were encountered in a unique haplotype. The diversity of these mutations reflects the historical admixture of genes in the region. The high prevalence of IVSII-1 (G-A) compared to other parts of the country and the world suggests a founder effect. Our data provide a basis for genetic counseling and prenatal diagnosis.     

Distribution of beta-thalassemia mutations in the northern provinces of Iran

Beta-Thalassemia (thal) is one of the most common autosomal recessive disorders in Iran. There are more than two million carriers of beta-thal and over 15,000 people affected with beta-thal major who live in Iran. Prevalent mutations were identified by examining genomic DNAs isolated from 392 blood samples of beta-thal carriers from three northern provinces of Iran. Furthermore, 172 pregnant women were analyzed from the 196 couples who requested pregnant diagnosis for beta-thal. Allele identification was carried out using routine reverse dot-blot, amplification refractory mutation system (ARMS), and genomic sequencing. The most common mutation, IVS-II-1 (GA), is followed, in order of frequency, by codon 30 (GC), frameshift codons (FSC) 8,9 (+G), FSC 22/23/24 (-AAGTTGG), IVS-I-110 (GA), IVS-I-5 (GC), IVS-II-745 (CG), IVS-I-2 (TC), FSC 8 (-AA), IVS-I,3'-end (-25 bp), IVS-I-1 (GA), FSC 36/37 (-T), IVS-I-6 (TC), FSC 5 (-CT), -28 (AC), codon 37 (GA), IVS-II-2,3 (+11/-2), -30 (TA), and -88 (CA). We have also revealed the existence of five new mutations from northern Iran, one of which (codon 37) is the first reported for Iran. Furthermore, the rate of unknown mutations is significantly reduced in our study (about 6%). These results could help with establishing a center for prenatal diagnosis, prevention, and control of thalassemia in the northern provinces of Iran.     

Distribution of β-Thalassemia Mutations in the Northern Provinces of Iran

β-Thalassemia (thal) is one of the most common autosomal recessive disorders in Iran. There are more than two million carriers of β-thal and over 15,000 people affected with β-thal major who live in Iran. Prevalent mutations were identified by examining genomic DNAs isolated from 392 blood samples of β-thal carriers from three northern provinces of Iran. Furthermore, 172 pregnant women were analyzed from the 196 couples who requested pregnant diagnosis for β-thal. Allele identification was carried out using routine reverse dot-blot, amplification refractory mutation system (ARMS), and genomic sequencing. The most common mutation, IVS-II-1 (G→A), is followed, in order of frequency, by codon 30 (G→C), frameshift codons (FSC) 8,9 (+G), FSC 22/23/24 (?AAGTTGG), IVS-I-110 (G→A), IVS-I-5 (G→C), IVS-II-745 (C→G), IVS-I-2 (T→C), FSC 8 (?AA), IVS-I,3′-end (?25 bp), IVS-I-1 (G→A), FSC 36/37 (?T), IVS-I-6 (T→C), FSC 5 (?CT), ?28 (A→C), codon 37 (G→A), IVS-II-2,3 (+11/?2), ?30 (T→A), and ?88 (C→A). We have also revealed the existence of five new mutations from northern Iran, one of which (codon 37) is the first reported for Iran. Furthermore, the rate of unknown mutations is significantly reduced in our study (about 6%). These results could help with establishing a center for prenatal diagnosis, prevention, and control of thalassemia in the northern provinces of Iran.     

Geographical variation in populations of Phlebotomus (Paraphlebotomus) caucasicus (Diptera: Psychodidae) in Iran

A comparative morphological and molecular study was carried out on 11 different populations of Phlebotomus (Paraphlebotomus) caucasicus Marzinovsky 1917 caught in 7 provinces in Iran (2004-2005). Differences in the implantation level of the two distal spines of the style, the number of setae of the basal lobe of coxite, and the length of the third antennal segment, revealed the existence of two morphotypes within P. (Pa) caucasicus, a species having a confused history if we take into account an unclear synonymisation with Phlebotomus (Paraphlebotomus) grimmi Porchinsky 1874. Sequencing of mtDNA (a fragment of cytchromeB gene, tRNA for serine gene and a fragment of NADH1 gene) and Neighbour-Joining analysis showed a partial correlation between morphotypes and haplotypes. We also found a correlation between the latter and the geographical origin of the specimens. These results need further studies in order to appreciate the role of each morphotype/haplotype in the transmission of Leishmania major.