The role of biochemical testing in cystic fibrosis

@#Cystic fibrosis (CF) is a life-limiting autosomal recessive disorder as a result of CF transmembrane conductance regulator gene mutation. It has a wide range of disease severity in patients with the same genotype. Case report: A 5-year-old Malay boy with a history of recurrent pneumonia, presented with productive cough, fever and worsening tachypnoea. Physical examination revealed coarse crepitations, reduced breath sounds and clubbing. Biochemical investigations showed that he had respiratory type 2 failure as a result of bronchiectasis. Sweat conductivity done twice was raised supporting a diagnosis of CF. Other investigations such as bronchoscopy to look for congenital anomaly of the lung, infectious disease screening and tuberculosis, fungal and viral culture and sensitivity were negative. Further cascade screening revealed high sweat conductivity results in his siblings. Discussion: Although CF prevalence is low in Malaysia, it is nevertheless an important diagnosis to be recognised as it is associated with increased morbidity.

Research progress on genetic mutation of congenital cataract / 国际眼科杂志(Guoji Yanke Zazhi)

@#Cataract is a kind of eye disease that causes lens metabolic disorder and protein degeneration and turbidity due to various reasons. Congenital cataract is especially serious. It is a common eye disease that affects the visual development of infants. It can inhibit the development of visual pathway and cause permanent blindness. About one-third of the cases are genetically related, of which autosomal dominant inheritance is the most common genetic mode. It's occurrence and development may be related to genes involved in lens development. Up to now, hundreds of mutation sites in more than 40 genes have been found to be associated with congenital cataract. This article will review the genetic research progress of congenital cataract.

The effect of methyl jasmonate on Zea mays tassel development / O efeito de methyl jasmonato sobre o devolvimento do pendão de Zea mays

Methyl jasmonate (MeJA) is a lipid-derived plant hormone that mediates diverse biological phenomena. Application of MeJA onto rice spikelet could exhibit abnormal floral organ development. Although jasmonic acid (JA) has been proved to be involved in maize tassel sex determination process, the roles of JA and its precursor MeJA in maize tassel development still remain obscure. In this study, we found that tassel development was decelerated by application of 2 mM MeJA. Exogenous MeJA also influenced the number of palea and stamens of tassel spikelets. Exogenous MeJA increased the expression level of some key regulator genes, which may responsible for the phenotypic change in MeJA-treated tassel, and may mediate the crosstalk between MeJA and other hormones.

jasmonate (MeJA) é um derivado lipídico vegetal hormônio que medeia Diversos fenómenos biológicos.Aplicação de MeJA para arroz spikelet poderá apresentar Desenvolvimento anormal DOS órgãos florais.Apesar de Ácido jasmónico (Ja), precursor de MeJA, mostrou ser envolvido no processo de determinação do sexo de milho tassel, OS papéis DOS dois compostos de milho tassel Desenvolvimento ainda permanecem obscuros.No presente estudo, descobrimos que o Desenvolvimento FOI desacelerada pelo pedido do tassel de 2 mm MeJA.MeJA exógeno também influenciou o número de palea e estames de tassel spikelets.MeJA aumentou o nível de expressão exógena, um regulador chave genes, o que Pode o responsável PELA alteração fenotípica EM MeJA tratados tassel, e podem mediar a interferência entre MeJA e outras hormonas.

Cystic fibrosis transmembrane conductance regulator (CFTR) gene abnormalities in Indian males with congenital bilateral absence of vas deferens & renal anomalies.

Background & objectives: The role of cystic fibrosis transmembrane conductance regulator (CFTR) gene mutations in congenital bilateral absence of vas deferens and unilateral renal agenesis (CBAVD-URA) has been controversial. Here, we report the cases of five Indian males with CBAVD-URA. The objective was to evaluate the presence or absence of CFTR gene mutations and variants in CBAVD-URA. The female partners of these males were also screened for cystic fibrosis (CF) carrier status. Methods: Direct DNA sequencing of CFTR gene was carried out in five Indian infertile males having CBAVD-URA. Female partners (n=5) and healthy controls (n=32) were also screened. Results: Three potential regulatory CFTR gene variants (c.1540A>G, c.2694T>G and c.4521G>A) were detected along with IVS8-5T mutation in three infertile males with CBAVD-URA. Five novel CFTR gene variants (c.621+91A>G, c.2752+106A>T, c.2751+85_88delTA, c.3120+529InsC and c.4375-69C>T), four potential regulatory CFTR gene variants (M470V, T854T, P1290P, Q1463Q) and seven previously reported CFTR gene variants (c.196+12T>C, c.875+40A>G, c.3041-71G>C, c.3271+42A>T, c.3272-93T>C, c.3500-140A>C and c.3601-65C>A) were detected in infertile men having CBAVD and renal anomalies Interpretation & conclusions: Based on our findings, we speculate that CBAVD-URA may also be attributed to CFTR gene mutations and can be considered as CFTR-related disorder (CFTR-RD). The CFTR gene mutation screening may be offered to CBAVD-URA men and their female partners undergoing ICSI. Further studies need to be done in a large sample to confirm the findings.

Detection of genotype and toxin associated gene of hypervirulent Clostridium difficile clinical isolates / 国际检验医学杂志

Objective To investigate the genotype and variance of toxin associated genes of moxifloxacin‐resistant Clostridium difficile clinical isolates in Sydney .Methods Twenty‐two moxifloxacin‐resistant Clostridium difficile clinical isolates were collected from Sydney ,which were genotyped by using sequencer capillary gel electrophoresis based PCR‐ribotyping ,and toxin A and B cod‐ing gene tcdA and tcdB ,and binary toxin coding gene cdtA and cdtB were detected by using PCR method .Toxin regulator gene tc‐dC was analyzed by using PCR‐sequencing ,and was aligned with reference sequence of VPI 10463 (Genbank accession number :X92982) ,and the tcdC sequence types of all 22 isolates were identified by using blast tool in NCBI .Results Twenty‐one isolates were genotyped as hypervirulent PCR‐ribotypes 027 (RT027) ,and one isolate as RT078 ;all 22 isolates contained tcdA and tcdB for toxin A and B and cdtA and cdtB for binary toxin (tcdA+ tcdB+ cdtA+ cdtB+ ) .The tcdC sequence types of the 21 RT027 i‐solates belong to sc1 ,and that of the one RT078 isolate belongs to WA39 .Compared with tcdC reference sequence of VPI 10463 ,a consecutive 18 bp deletion (nt341 to 379) and one nucleotide deletion at position 117 were found in the 21 RT027 isolates ,and a consecutive 39 bp deletion (nt330 to 368) and one nucleotide mutation at position 184(C> T) were found in the one RT078 isolate . Conclusion Clostridium difficile hypervirulent RT027 was the common moxifloxacin resistant genotype ;Clostridium difficile hy‐pervirulent RT027 and RT078 clinical isolates contained genes for toxin A and B and binary toxin ,and contained gene sequence mu‐tation in toxin regulator gene tcdC .

Progress in molecular genetics in autoimmune polyendocrinopathy syndrome type Ⅰ / 国际儿科学杂志

Autoimmune polyendocrinopathy syndrome type Ⅰ( APS-Ⅰ) is a rare autosomal recessive disorder caused by mutations in autoimmune regulator gene( AIRE) . A number of mutations have been described in the AIRE gene of patients with APS-Ⅰ, including nonsense mutation, missense mutation, silent mutation, splice site mutation, insertions and deletions mutation, et al. The mutation characteristics of the APS-Ⅰ pathogenic gene have been reviewed in the article.