Stability of unfrozen whole blood DNA for remote genotypic analysis of HIV-1 coreceptor tropism

Maraviroc is an HIV-1 coreceptor antagonist that has shown good efficacy and tolerability in treatment-naive and treatment-experienced patients harboring CCR5-tropic virus. The use of Maraviroc in treatment simplification in patients with suppressed plasma HIV-1 RNA requires analysis of HIV-1 DNA. Coreceptor tropism testing is often performed remotely at reference laboratories. In this study paired whole blood stored at + 4 °C and at-20°C were compared as a source for genotypic coreceptor tropism testing

Age-specific effects of estrogen receptors' polymorphisms on the bone traits in healthy fertile women: the BONTURNO study

<p>Abstract</p> <p>Background</p> <p>Skeletal characteristics such as height (Ht), bone mineral density (BMD) or bone turnover markers are strongly inherited. Common variants in the genes encoding for estrogen receptor alpha (ESR1) and beta (ESR2) are proposed as candidates for influencing bone phenotypes at the population level.</p> <p>Methods</p> <p>We studied 641 healthy premenopausal women aged 20–50 years (yrs) participating into the BONTURNO study. Exclusion criteria were irregular cyclic menses, low trauma fracture, metabolic bone or chronic diseases. Serum C-telopeptide of type I collagen (CTX), osteocalcin (OC), and N-terminal propeptide of type I procollagen (P1NP) were measured in all enrolled subjects, who underwent to lumbar spine (LS), total hip (TH) and femoral neck (FN) BMD evaluation by DXA. Five hundred seventy Caucasian women were genotyped for ESR1 rs2234693 and rs9340799 and ESR2 rs4986938 polymorphisms.</p> <p>Results</p> <p>Although no genotype differences were found in body parameters, subjects with combined ESR1 CCGG plus ESR2 AA-AG genotype were taller than those with opposite genotype (P = 0.044). Moreover, ESR1 rs2234693 genotypes correlated with family history of osteoporosis (FHO) and hip fracture (FHF) (P < 0.01), while ESR2 AA-AC genotypes were strongly associated with FHF (OR 2.387, 95% CI 1.432–3.977; P < 0.001).</p> <p>When clustered by age, 20–30 yrs old subjects, having at least one ESR1 rs2234693 C allele presented lower LS- (P = 0.008) and TH-BMD (P = 0.047) than TT genotypes. In 41–50 yrs age, lower FN-BMD was associated with ESR2 AA (P = 0.0180) subjects than in those with the opposite genotype. ESR1 rs2234693 and rs9340799 and ESR2 rs4986938 polymorphisms did not correlate with age-adjusted values of OC, CTX and P1NP.</p> <p>Conclusion</p> <p>These findings support the presence of age-specific effects of ESR1 and ESR2 polymorphisms on various skeletal traits in healthy fertile women.</p

Comparative analysis between saliva and buccal swabs as source of DNA: lesson from HLA-B*57:01 testing

Aim: Our work aimed to designate the optimal DNA source for pharmacogenetic assays, such as the screening for HLA-B*57:01 allele. Materials & methods: A saliva and four buccal swab samples were taken from 104 patients. All the samples were stored at different time and temperature conditions and then genotyped for the HLA-B*57:01 allele by SSP-PCR and classical/capillary electrophoresis. Results: The genotyping analysis reported different performance rates depending on the storage conditions of the samples. Given our results, the buccal swab demonstrated to be more resistant and stable in time with respect to the saliva. Conclusion: Our investigation designates the buccal swab as the optimal DNA source for pharmacogenetic assays in terms of resistance, low infectivity, low-invasiveness and easy sampling, and safe transport in centralized medical centers providing specialized pharmacogenetic tests

Novel sensitive, specific and rapid pharmacogenomic test for the prediction of abacavir hypersensitivity reaction: HLA-B*57:01 detection by real-time PCR.

Aim: International HIV treatment guidelines recommend HLA-B*57:01 typing before abacavir administration, in order to reduce the incidence of abacavir hypersensitivity reactions, the major cause of early therapy discontinuation. A fast, sensitive and specific test for HLA-B*57:01 detection has been developed in the present study. Materials & methods: Two sets of sequence-specific primers were designed, and amplification rapidly detected by real-time PCR. Results: A total of 108 samples were analyzed in a single-blind fashion, and 41 samples were identified as positive. Complete agreement, with k = 1 (standard error = 0.0962, p < 0.0001), was found, with a validated methodology used in the EPI109367 clinical trial funded by GlaxoSmithKline, and consisting of low-resolution sequence-specific oligonucleotide PCR, followed by high-resolution sequence-specific oligonucleotide PCR carried out on the HLA-B*57-positive samples. Conclusion: We provided a detailed characterization of a novel HLA-B*57:01 screening test, which can be easily implemented by those laboratories already involved in the detection of viral load and virus genotyping

Comparative Analysis of Real-Time Polymerase Chain Reaction Methods to Typing HLA-B*57:01 in HIV-1-Positive Patients

The HLA-B*57:01 allele is strongly associated with the hypersensitivity reaction to Abacavir (ABC). Therefore, treatment guidelines recommend that patients initiating ABC are preventively tested for the presence of this allele. To date, four different commercial assays based on the real-time quantitative polymerase chain reaction (Q-PCR) technique are available for the detection of HLA-B*57:01: Duplicα-RealTime Reagent Set HLA-B*57:01 by Euroclone, HLA-B*57:01 Real-TM by Sacace Biotechnologies, COBAS AmpliPrep/COBAS TaqMan HLA-B*57:01 Screening Test by Roche Diagnostic, and HLA-B*57:01 by Nuclear Laser Medicine. The study was carried out to compare the performance of the first three commercially available Q-PCR kits in a routine clinical setting. A total of 98 samples from Policlinico Umberto I Hospital were tested. Results obtained by the Duplicα-RealTime Genotyping kit and AmpliPrep/TaqMan system were 100% concordant. In contrast, genotyping by the HLA-B*57:01 Real-TM kit showed poor agreement with the other systems, that is, 12 out of 33 positive samples were detected as HLA-B*57:01 negative. To confirm the correct genotype of these discordant samples, two additional methods with rapid turnaround times and already implemented into routine clinical practice were used, that is, a PCR-based microsequence-specific primer DNA typing test and a laboratory-developed screening test in Q-PCR. All 12 discordant samples were genotyped as HLA-B*57:01-positive samples using these two additional methods in a single-blinded manner, thus confirming the low sensitivity of HLA-B*57:01 Real-TM test. These findings underline the need to compare results obtained with commercial assays before choosing a test suitable for use in a routine clinical laboratory

Un quadrivio: pensiero, societ\ue0, arti e lettere, natura

Recensione al volume: ETTORE SOTTSASS, Molto difficile da dire, a cura di Matteo Codignola, Adelphi, Milano, 2019