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Objective The presence of primary hyperparathyroidism (PHPT) and Klinefelter syndrome (KS) is rare, and its association with KS mosaicism is even rarer. We report an unusual combination of these entities with a mild phenotype of KS. Methods The patient was a 44-year-old male with a history of PHPT who had recurrent urolithiasis despite being treated with a successful parathyroidectomy. On examination, he had axillary hair growth, bilateral gynecomastia, a large port-wine stain at the right hemithorax and upper right limb, and genitalia and pubic hair corresponding to Tanner IV classification with small, normal consistency testicles. Results Laboratory findings were unremarkable except for a slightly elevated luteinizing hormone, which was normal on repeat testing. Because of the picture of unexplained gynecomastia, laboratory findings, and low-volume testis, a diagnosis of KS was considered. Chromosomal analysis revealed a rare 45,X/46,XY/47,XXY/48,XXYY/48,XXXY KS mosaic. Conclusions KS phenotypes are largely variable, and their association with PHPT remains to be elucidated.

BACKGROUND AND AIMS: Familial hypertriglyceridemia (FHTG) is a partially characterized primary dyslipidemia which is frequently confused with other forms hypertriglyceridemia. The aim of our study is to search for specific features that help clinicians in the recognition of FHTG. APPROACH: We included 84 FHTG cases, 728 subjects with mild-to-moderate hypertriglyceridemia (CHTG) and 609 normotriglyceridemic controls for genetic, clinical and biochemical assessment. A set of 53 SNPs previously associated to TG levels, as well as 37 rare variants within the main five genes associated to hypertriglyceridemia (i.e. LPL, APOC2, APOA5, LMF1 and GPIHBP1) were analyzed. A panel of endocrine regulatory proteins closely related to triglycerides homeostasis were compared between FHTG and CHTG.RESULTS: Compared to CHTG, FHTG subjects had higher HOMA-IR, apolipoprotein AII, FGF21, ANGPTL3 and ANGPTL4 concentrations and lower HOMA-B%, apolipoprotein B and leptin. The polygenic set of SNPs, previously associated with triglyceride levels, accounted for 1.78% of the explained variance of triglyceride levels in FHTG and 6.73% in CHTG. CONCLUSION: The clinical and genetic differences observed between FHTG and CHTG supports the notion that FHTG is a unique entity, distinguishable from other causes of hypertriglyceridemia by the higher concentrations of insulin, FGF21, ANGPTL3, apoAII and lower levels of apoB. We propose the inclusion of these analytes as useful markers to distinguish FHTG from other causes of hypertriglyceridemia.

Background Familial hypertriglyceridemia (FHTG) is a partially characterized primary dyslipidemia which is frequently confused with other forms hypertriglyceridemia. The aim of this work is to search for specific features that can help physicians recognize this disease. Methods This study included 84 FHTG cases, 728 subjects with common mild-to-moderate hypertriglyceridemia (CHTG) and 609 normotriglyceridemic controls. All subjects underwent genetic, clinical and biochemical assessments. A set of 53 single nucleotide polymorphisms (SNPs) previously associated with triglycerides levels, as well as 37 rare variants within the five main genes associated with hypertriglyceridemia (i.e. LPL, APOC2, APOA5, LMF1 and GPIHBP1) were analyzed. A panel of endocrine regulatory proteins associated with triglycerides homeostasis were compared between the FHTG and CHTG groups. Results Apolipoprotein B, fibroblast growth factor 21(FGF-21), angiopoietin-like proteins 3 (ANGPTL3) and apolipoprotein A-II concentrations, were independent components of a model to detect FHTG compared with CHTG (AUC 0.948, 95%CI 0.901–0.970, 98.5% sensitivity, 92.2% specificity, P Conclusions The clinical and genetic differences observed between FHTG and CHTG supports the notion that FHTG is a unique entity, distinguishable from other causes of hypertriglyceridemia by the higher concentrations of insulin, FGF-21, ANGPTL3, apo A-II and lower levels of apo B. We propose the inclusion of these parameters as useful markers for differentiating FHTG from other causes of hypertriglyceridemia.

Type 2 diabetes (T2D) affects more than 415 million people worldwide, and its costs to the health care system continue to rise. To identify common or rare genetic variation with potential therapeutic implications for T2D, we analyzed and replicated genome-wide protein coding variation in a total of 8,227 individuals with T2D and 12,966 individuals without T2D of Latino descent. We identified a novel genetic variant in the IGF2 gene associated with ∼20% reduced risk for T2D. This variant, which has an allele frequency of 17% in the Mexican population but is rare in Europe, prevents splicing between IGF2 exons 1 and 2. We show in vitro and in human liver and adipose tissue that the variant is associated with a specific, allele-dosage–dependent reduction in the expression of IGF2 isoform 2. In individuals who do not carry the protective allele, expression of IGF2 isoform 2 in adipose is positively correlated with both incidence of T2D and increased plasma glycated hemoglobin in individuals without T2D, providing support that the protective effects are mediated by reductions in IGF2 isoform 2. Broad phenotypic examination of carriers of the protective variant revealed no association with other disease states or impaired reproductive health. These findings suggest that reducing IGF2 isoform 2 expression in relevant tissues has potential as a new therapeutic strategy for T2D, even beyond the Latin American population, with no major adverse effects on health or reproduction.

Dyslipidemias are common risk factors for the development of chronic disorders including type 2 diabetes (T2D). Over 100 associated loci have been identified but few reports have evaluated the population attributable fraction captured by them in population-based nationwide surveys. Therefore, we determined the population contribution of a set of known genetic risk variants to the development of dyslipidemias and T2D in Mexico. This study included 1665 participants from a Mexican National Health Survey carried out in the year 2000. It is a probabilistic complex sample survey of households, which comprises representative data at a national level. 103 previously reported SNPs associated with different dyslipidemias or T2D were genotyped and used to compute polygenic risk scores. We found that the previously known variants associated with dyslipidemias explain at most 7% of the total risk variance of lipid levels. In contrast, the known genetic risk component for T2D explained a negligible amount of variance (0.1%). Notably, variants derived from the Native-American ancestry have the strongest effect and contribute with a high proportion of the variance. These results support the need for additional studies aimed to identify specific genetic risk variants for Mexican population.

Type 2 diabetes (T2D) affects more than 415 million people worldwide, and its costs to the health care system continue to rise. To identify common or rare genetic variation with potential therapeutic implications for T2D, we analyzed and replicated genome-wide protein coding variation in a total of 8,227 individuals with T2D and 12,966 individuals without T2D of Latino descent. We identified a novel genetic variant in the IGF2 gene associated with ∼20% reduced risk for T2D. This variant, which has an allele frequency of 17% in the Mexican population but is rare in Europe, prevents splicing between IGF2 exons 1 and 2. We show in vitro and in human liver and adipose tissue that the variant is associated with a specific, allele-dosage–dependent reduction in the expression of IGF2 isoform 2. In individuals who do not carry the protective allele, expression of IGF2 isoform 2 in adipose is positively correlated with both incidence of T2D and increased plasma glycated hemoglobin in individuals without T2D, providing support that the protective effects are mediated by reductions in IGF2 isoform 2. Broad phenotypic examination of carriers of the protective variant revealed no association with other disease states or impaired reproductive health. These findings suggest that reducing IGF2 isoform 2 expression in relevant tissues has potential as a new therapeutic strategy for T2D, even beyond the Latin American population, with no major adverse effects on health or reproduction.

The burden caused by familial hypercholesterolemia (FH) varies among countries and ethnic groups. The prevalence and characteristics of FH in Latin American (LA) countries is largely unknown. We present a systematic review (following the PRISMA statement) of FH in LA countries. The epidemiology, genetics, screening, management, and unique challenges encountered in these countries are discussed. Published reports discussing FH in Hispanic or LA groups was considered for analysis. Thirty studies were included representing 10 countries. The bulk of the data was generated in Brazil and Mexico. Few countries have registries and there was little commonality in FH mutations between LA countries. LDL receptor mutations predominate; APOB and PCSK9 mutations are rare. No mutation was found in an FH gene in nearly 50% of cases. In addition, some country-specific mutations have been reported. Scant information exists regarding models of care, cascade screening, cost, treatment effectiveness, morbidity, and mortality. In conclusion, FH is largely underdiagnosed and undertreated in the LA region. The genetic admixture with indigenous populations, producing mestizo's groups, may influence the mutational findings in Latin America. Potential opportunities to close gaps in knowledge and health care are identified.

Type 2 diabetes (T2D) affects Latinos at twice the rate seen in populations of European descent. We recently identified a risk haplotype spanning SLC16A11 that explains ∼20% of the increased T2D prevalence in Mexico. Here, through genetic fine-mapping, we define a set of tightly linked variants likely to contain the causal allele(s). We show that variants on the T2D-associated haplotype have two distinct effects: (1) decreasing SLC16A11 expression in liver and (2) disrupting a key interaction with basigin, thereby reducing cell-surface localization. Both independent mechanisms reduce SLC16A11 function and suggest SLC16A11 is the causal gene at this locus. To gain insight into how SLC16A11 disruption impacts T2D risk, we demonstrate that SLC16A11 is a proton-coupled monocarboxylate transporter and that genetic perturbation of SLC16A11 induces changes in fatty acid and lipid metabolism that are associated with increased T2D risk. Our findings suggest that increasing SLC16A11 function could be therapeutically beneficial for T2D. Video Abstract [Figure presented] Keywords: type 2 diabetes (T2D); genetics; disease mechanism; SLC16A11; MCT11; solute carrier (SLC); monocarboxylates; fatty acid metabolism; lipid metabolism; precision medicine

The expression and biological role of actin during the Trypanosoma cruzi life cycle remains largely unknown. Polyclonal antibodies against a recombinant T. cruzi actin protein were used to confirm its expression in epimastigotes, trypomastigotes, and amastigotes. Although the overall levels of expression were similar, clear differences in the subcellular distribution of actin among the developmental stages were identified. The existence of five actin variants in each developmental stage with distinct patterns of expression were uncovered by immunoblotting of protein extracts separated 2D-SDS gels. The isoelectric points of the actin variants in epimastigotes ranged from 4.45 to 4.9, whereas they ranged from 4.9 to 5.24 in trypomastigotes and amastigotes. To determine if the actin variants found could represent previously unidentified actins, we performed a genomic survey of the T. cruzi GeneDB database and found 12 independent loci encoding for a diverse group of actins and actin-like proteins that are conserved among trypanosomatids.

BACKGROUND: The cytogenetic aspects of acute leukemia have been studied for over 30 years. Genomic sequencing has permitted the identification of recurrent mutations that have been associated with the heterogeneous behavior of acute leukemia. Currently, the genomic profile of patients with acute leukemia is important regarding risk classification and therapeutic approach. At this moment there are scarce studies of the genomic profile in adult patients with acute leukemia in Mexico. OBJECTIVES: To describe genomic alterations found in adult patients with acute leukemia in a cancer reference hospital in Mexico. Evaluate the efficacy of a commercial multiple PCR and nested qualitative PCR kit (HemaVision DNA Technology A/S, HV01-28N), for the detection of 28 translocations on acute leukemia. To assess by a quantitative method with RT-PCR the detection of the most frequently reported mutations in acute myeloid leukemia(38%) [t(15;17) PML-RARa, inv(16) CBF-MYH11, t(8;21) RUNX1-RUNX1T1 and acute lymphoid leukemia (32%) [t(9;22) BCR/ABL, t(4;11) MLL-AFF1, t(1;19) TCF3-PBX1]. Compare the results between the commercial kit, RT-PCR and conventional cytogenetic studies. METHODS: Patients with recent diagnosis of acute leukemia (myeloid and lymphoid) according to World Health Administration (WHO) 2008 criteria were included between the period of 03/25/2013 and 12/15/13. All patients were given informed consent form and approval of the local Ethics Committee We performed bone marrow smear and bone marrow biopsy of all patients. 5 mL of bone marrow were collected on heparin for cytogenetic study including karyotipe and FISH analysis. 5 mL of bone marrow were collected for molecular biology studies including PCR-kit and genome sequencing technique. 5mL of peripheral blood with heparin were obtained for karyotype in case of not finding metaphases for the analysis on bone marrow specimen. RESULTS: 24 patients were enrolled on the study. The mean age was 42 years (17-69). 8/24 were male (33.3%) and 16/24 were female (66.6%). Acute myeloid leukemia 11/24 (45.8%), acute lymphoblastic leukemia 8/24 (33.3%), acute promyeolocytic leukemia 3/24 (12.5%), acute biphenotypic leukemia 1/24 (4.2%) and one case of blastic phase of chronic myeloid leukemia (4.2%). The commercial PCR platform detected only two of the 28 translocations in 4/24 patients (16.6%). 2/24 (8.3%) BCR-ABL and 2/24 (8.3%) PML-RARa. In contrast to RT-PCR that detected 7/24 patients (29%). 4/24 (16%) BCR-ABL, 2/24 (8.3%) PML-RARa and 1/24 (4.1%) CBFB-MYH11. FISH analysis detected the 4/24 (16%) translocations of the commercial kit. Karyotype detected structural chromosomal anomalies in 9/24 patients (37.5%). After the analysis of the 24 samples by quantitative RT-PCR for the six most frequent rearrangements, we also identified 2 additional cases of BCR-ABL. CONCLUSIONS: The commercial qualitative PCR kit was inferior on detecting genomic alterations (16.6%) than quantitative PCR (29%) or conventional cytogenetic study (37.5%). The RT-PCR quantitative method with specific probe for the most frequent genomic alterations in acute leukemia in addition to cytogenetic analysis seems to be a better cost-effective strategy than the commercial multiple PCR platforms. Disclosures No relevant conflicts of interest to declare.