Molecular defects identified by whole exome sequencing in a child with Fanconi anemia

Fanconi anemia is a rare genetic disease characterized by bone marrow failure, multiple congenital malformations, and an increased susceptibility to malignancy. At least 15 genes have been identified that are involved in the pathogenesis of Fanconi anemia. However, it is still a challenge to assign the complementation group and to characterize the molecular defects in patients with Fanconi anemia. In the current study, whole exome sequencing was used to identify the affected gene(s) in a boy with Fanconi anemia. A recurring, non-synonymous mutation was found (c.3971C>T, p.P1324L) as well as a novel frameshift mutation (c.989_995del, p.H330LfsX2) in FANCA gene. Our results indicate that whole exome sequencing may be useful in clinical settings for rapid identification of disease-causing mutations in rare genetic disorders such as Fanconi anemia.     

Two newly identified exons in human GRM1 express a novel splice variant of metabotropic glutamate 1 receptor

To date, five human metabotropic glutamate (mGlu) 1 receptor splice variants (1a, 1b, 1d, 1f, and 1g) have been described, all of which involve alternative C-terminal splicing. mGlu1a receptor contains a long C-terminal domain (341 amino acids), which has been shown to scaffold with several proteins and contribute to the structure of the post-synaptic density. However, several shorter mGlu1 receptor splice variants lack the sequence required for these interactions, and no major functional differences between these short splice variants have been described. By using RT-PCR we have shown that two human melanoma cell lines express both mGlu1a and mGlu1b receptors. In addition, using 3′RACE, we identified three previously unknown mGlu1 receptor mRNAs. Two differ in the length of their 3′ untranslated region (UTR), and encode the same predicted protein as mGlu1g receptor—the shortest of all mGlu1 receptor splice variants. The third mRNA, named mGlu1h, encodes a predicted C-terminal splice variant of 10 additional amino acids. mGlu1h mRNA was observed in two different melanoma cell lines and is overexpressed, compared with melanoma precursor cells, melanocytes. Most importantly, this new splice variant, mGlu1h receptor, is encoded by two previously unidentified exons located within the human GRM1 gene. Additionally, these new exons are found exclusively within the GRM1 genes of higher primates and are highly conserved. Therefore, we hypothesize that mGlu1h receptors play a distinct role in primate glutamatergic signaling.     

单头亚菊的组织培养与快速繁殖

以单头亚菊茎段为外植体对其进行组织培养,MS为基本培养基,设置不同激素浓度配比。对实验结果进行观察分析,筛选出合适的配方。启动培养基为Ms＋0．5mg·L-16-BA＋0．01mg·L-1NAA。继代培养基MS＋O．75mg·L-1。6-BA＋0．01mg·L。NAA,可获得较高的增殖率。不定根最适诱导培养基为1／2MS＋O．15mg·L—IBA,生根率达87％以上,组培苗移栽成活率达98％。     

Molecular cloning and characterization of an Hsp90/70 organizing protein gene from Frankliniella occidentalis (Insecta: Thysanoptera,Thripidae)

The heat shock 90/70 organizing protein (Hop), also known as Sti-1 (stress-induced protein-1), is a co-chaperone that usually mediates the interaction of Hsp90 and Hsp70 and has been extensively characterized in mammals and plants. However, its role in insects remains unknown. In the present study, we isolated and characterized a Hop homologue gene from Frankliniella occidentalis (Fohop). The Fohop contains a 1659 bp ORF encoding a protein of 552 amino acids with a caculated molecular mass of approximately 62.25 kDa, which displays a reasonable degree of identity with the known Hops and shares several canonical motifs, including three tetratricopeptide repeated motif domains (TPR1, TPR2A and TPR2B) and two aspartic acid–proline (DP) repeat motifs (DP1 and DP2). As in other hops, Fohop contains introns, but the number and the position are quite variable. The mRNA expression patterns indicated that Fohop was constitutively expressed throughout the developmental stages, but was obviously upregulated by heat stress both in larvae and adults. Our studies imply that Hop, as in other Hsps, may play an important role in heat shock response of F. occidentalis.     

Book review

Oral Biofilms and Plaque Control. Edited by H J Busscher and L V Evans. Harwood Academic Publishers, The Netherlands, 1998; 348 pp, US$ 125.00; £80.00; ISBN 90–5702–391–1     

Bipolar Disorder with Seasonal Pattern: Clinical Characteristics and Gender Influences

Bipolar disorder (BD) has a multifactorial etiology with heterogeneous clinical presentations. Around 25% of BD patients may present with a depressive seasonal pattern (SP). However, there are limited scientific data on the prevalence of SP, its clinical manifestations, and any gender influence. Four hundred and fifty-two BD I and II cases (62% female), recruited from three French university-affiliated psychiatric departments, were assessed for SP. Clinical, treatment, and sociodemographic variables were obtained from structured interviews. One hundred and two (23%) cases met DSM-IV (Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition) criteria for SP, with similar frequency according to gender. Multivariate analysis showed a significant association between SP and BD II (odds ratio [OR]?=?1.99, p?=?0.01), lifetime history of rapid cycling (OR?=?2.05, p?=?0.02), eating disorders (OR?=?2.94, p?=?0.003), and total number of depressive episodes (OR?=?1.13, p?=?0.002). Seventy-one percent of cases were correctly classified by this analysis. However, when stratifying the analyses by gender, SP was associated with BD II subtype (OR?=?2.89, p?=?0.017) and total number of depressive episodes (OR?=?1.21, p?=?0.0018) in males but with rapid cycling (OR?=?3.02, p?=?0.0027) and eating disorders (OR?=?2.60, p?=?0.016) in females. This is the first study to identify different associations between SP and clinical characteristics of BD according to gender. The authors suggest that SP represents a potentially important specifier of BD. These findings indicate that seasonality may reflect increased severity or complexity of disorder.     

Molecular Diagnosis of an Ocular Toxocariasis Patient in Vietnam

An ocular Toxocara canis infection is reported for the first time in Vietnam. A 34-year-old man residing in a village of Son La Province, North Vietnam, visited the National Eye Hospital (NEH) in August 2011. He felt a bulge-sticking pain in his left eye and loss of vision occurred over 3 months before visiting the hospital. The eye examination in the hospital showed damage of the left eye, red eye, retinal fibrosis, retinal detachment, inflammation of the eye tissues, retinal granulomas, and a parasitic cyst inside. A larva of Toxocara was collected with the cyst by a medical doctor by surgery. Comparison of 264 nucleotides of internal transcribed spacer 2 (ITS2) of ribosomal DNA was done between our Vietnamese Toxocara canis and other Toxocara geographical isolates, including Chinese T. canis, Japanese T. canis, Sri Lankan T. canis, and Iranian T. canis. The nucleotide homology was 97-99%, when our T. canis was compared with geographical isolates. Identification of a T. canis infection in the eye by a molecular method was performed for the first time in Vietnam.