Lipoprotein profile assessed by 1H NMR, BMI and blood pressure are associated with vascular alterations in children with familial hypercholesterolaemia.

BACKGROUND AND AIMS: Children with familial hypercholesterolaemia (FH) have elevated low-density lipoprotein cholesterol (LDL-C) concentrations since birth, which increases the risk of cardiovascular disease in adulthood. Arterial injury and stiffness parameters, including carotid intima media thickness (cIMT), pulse wave velocity (PWV) and distensibility (DIST), can be detected early in childhood. We studied the associations between cIMT, PWV and DIST with the lipoprotein profile assessed by proton nuclear magnetic resonance (1H NMR) and with influential variables such as blood pressure (BP) or body mass index (BMI) in children with FH. METHODS AND RESULTS: In this cross-sectional study, we included 201 children (96 with FH and 105 non-FH controls). Clinical history, physical examination and standard biochemical studies were performed. FH genetic testing was performed when clinically indicated. Carotid ultrasonography and an advanced lipoprotein profile by 1H NMR were performed. Multivariate and classification methods were used. There were no differences between cIMT, PWV and DIST between FH and non-FH children. FH children presented more total LDL and large, medium and small particles. Small LDL particles, BMI and systolic BP determined the presence of pathological IMT in the FH group. LDL size, high-density lipoproteins and very low-density lipoprotein particles together with blood pressure determined the presence of pathological arterial wall elasticity. CONCLUSIONS: Alterations in lipoprotein parameters assessed by are associated with early structural and functional arterial characteristics in children with FH. BMI and BP act as boosting factors. Cardiovascular prevention should start early in children with FH, encompassing all components of a healthy lifestyle.

Mental performance in 8-year-old children fed reduced protein content formula during the 1st year of life: safety analysis of a randomised clinical trial.

In humans, maximum brain development occurs between the third trimester of gestation and 2 years of life. Nutrition during these critical windows of rapid brain development might be essential for later cognitive functioning and behaviour. In the last few years, trends on protein recommendations during infancy and childhood have tended to be lower than that in the past. It remains to be demonstrated that lower protein intakes among healthy infants, a part of being able to reduce obesity risk, is safe in terms of mental performance achievement. Secondary analyses of the EU CHOP, a clinical trial in which infants from five European countries were randomised to be fed a higher or a lower protein content formula during the 1st year of life. Children were assessed at the age of 8 years with a neuropsychological battery of tests that included assessments of memory (visual and verbal), attention (visual, selective, focused and sustained), visual-perceptual integration, processing speed, visual-motor coordination, verbal fluency and comprehension, impulsivity/inhibition, flexibility/shifting, working memory, reasoning, visual-spatial skills and decision making. Internalising, externalising and total behaviour problems were assessed using the Child Behaviour Checklist 4-18. Adjusted analyses considering factors that could influence neurodevelopment, such as parental education level, maternal smoking, child's gestational age at birth and head circumference, showed no differences between feeding groups in any of the assessed neuropsychological domains and behaviour. In summary, herewith we report on the safety of lower protein content in infant formulae (closer to the content of human milk) according to long-term mental performance.

Association of early protein intake and pre-peritoneal fat at five years of age: Follow-up of a randomized clinical trial.

BACKGROUND AND AIMS: The double-blind randomized European Childhood Obesity Project (CHOP) demonstrated that reduced protein content in infant formula leads to a lower body mass index (BMI) up to six years of age. Here we aimed at assessing pre-peritoneal fat, a marker of visceral fat, in children participating in the CHOP trial. METHODS AND RESULTS: Healthy term formula-fed infants in five European countries were randomized either to higher (n = 550) or lower (n = 540) protein formulas in the first year of life. Infants who were exclusively breastfed for at least three months (n = 588) were enrolled as an observational (non randomized) group. At age 5 years, subcutaneous fat (SC) and pre-peritoneal fat (PP) were measured by ultrasound in a subgroup of 275 children. The PP fat layer was thicker in the higher compared to the lower protein group (adjusted estimated difference: 0.058 cm, 95%CI 0.002; 0.115; p = 0.043), while SC fat was not different. Girls showed a thicker SC fat layer than boys. CONCLUSIONS: Higher protein intake in formula-fed infants appears to enhance pre-peritoneal fat tissue accumulation at the age of 5 years, but not of subcutaneous fat, which may trigger adverse metabolic and health consequences.

Expression and characterization of the gD protein of HSV-2 fused to the tetramerization domain of the transcription factor p53.

The highly immunogenic glycoprotein D (gD) of herpes simplex virus type 2 (HSV-2) is a very important element for entry of this virus into host cells. These characteristics have made this protein a very interesting HSV-2 subunit vaccine candidate. Despite efforts to prevent genital herpes using gD-based subunit vaccines, to date, clinical trials using this antigen have failed. Therefore, using a small animal model, we sought to determine if a tetramerized truncated form of gD subunit vaccine, produced by recombinant baculovirus infected insect larvae, would elicit better protection against genital herpes than a monomeric gD-2 subunit vaccine. Three out of 5 mice immunized with the tetramerized antigen produced in a baculovirus expression vector system, survived a lethal challenge with a wild type HSV-2 strain (for more than 3 weeks after challenge). In contrast, all the mice (5) immunized with the truncated protein, produced by the same methodology, died within 2 weeks after challenge. These results suggest that multimerization (increasing the structural complexity) of the truncated gD antigen might be more likely protective than the monomer form. Also the use of an alternative cost-efficient eukaryotic expression system is described.

Modeling the formation of cell-matrix adhesions on a single 3D matrix fiber.

Cell-matrix adhesions are crucial in different biological processes like tissue morphogenesis, cell motility, and extracellular matrix remodeling. These interactions that link cell cytoskeleton and matrix fibers are built through protein clutches, generally known as adhesion complexes. The adhesion formation process has been deeply studied in two-dimensional (2D) cases; however, the knowledge is limited for three-dimensional (3D) cases. In this work, we simulate different local extracellular matrix properties in order to unravel the fundamental mechanisms that regulate the formation of cell-matrix adhesions in 3D. We aim to study the mechanical interaction of these biological structures through a three dimensional discrete approach, reproducing the transmission pattern force between the cytoskeleton and a single extracellular matrix fiber. This numerical model provides a discrete analysis of the proteins involved including spatial distribution, interaction between them, and study of the different phenomena, such as protein clutches unbinding or protein unfolding.

Cost analysis of sentinel lymph node biopsy in melanoma.

INTRODUCTION AND OBJECTIVE: Sentinel lymph node biopsy (SLNB) is the most useful tool for node staging in melanoma. SLNB facilitates selective dissection of lymph nodes, that is, the performance of lymphadenectomy only in patients with sentinel nodes positive for metastasis. Our aim was to assess the cost of SLNB, given that this procedure has become the standard of care for patients with melanoma and must be performed whenever patients are to be enrolled in clinical trials. Furthermore, the literature on the economic impact of SLNB in Spain is scarce. METHOD: From 2007 to 2010, we prospectively collected data for 100 patients undergoing SLNB followed by transhilar bivalving and multiple-level sectioning of the node for histology. Our estimation of the cost of the technique was based on official pricing and fee schedules for the Spanish region of Murcia. RESULTS: The rate of node-positive cases in our series was 20%, and the mean number of nodes biopsied was 1.96; 44% of the patients in the series had thin melanomas. The total cost was estimated at between €9486.57 and €10471.29. Histopathology accounted for a considerable portion of the cost (€5769.36). DISCUSSION: The cost of SLNB is high, consistent with amounts described for a US setting. Optimal use of SLNB will come with the increasingly appropriate selection of patients who should undergo the procedure and the standardization of a protocol for histopathologic evaluation that is both sensitive and easy to perform.

Results of a survey on albumin use in clinical practice in intensive care units.

BACKGROUND: Human albumin solutions are used in a number of disorders, though their indications are not clear in all circumstances. These solutions are costly, and their benefit has not been established in all settings. It is therefore interesting to assess the presence of albumin solutions in the daily clinical practice of critical care professionals. OBJECTIVES: To report the standard clinical practices and to describe the variability of albumin solutions use in critically ill patients. DESIGN: A survey sent by e-mail to Spanish and South American Intensive Care Units (ICUs) PERIOD: Planning and execution during the year 2012. METHODS: A questionnaire comprising 35 questions. RESULTS: Fifty-seven surveys were analyzed. The use of albumin solutions was sporadic or negligible in critically ill patients (96.5%). The exceptions were patients with liver disease (87.7% of the responders administered albumin to these patients). A high percentage of professionals claimed to know the available scientific evidence on the use of albumin in patients with liver disease (82.5%) and in patients without liver disease (77.2%). Only 5.3% of the responders preferred to rely on their own experience to establish the indications of albumin use. CONCLUSIONS: The use of albumin solutions is infrequent in ICUs, except in patients with liver disease. Evidence-based knowledge on albumin use is declared to be extensive in ICUs. As a rule, opinions on the use of albumin solutions are based on the scientific recommendations, especially in patients with liver disease. Professional experience rarely prevails over the published clinical guidelines.

Co-inheritance of HNF1a and GCK mutations in a family with maturity-onset diabetes of the young (MODY): implications for genetic testing.

OBJECTIVE: To determine the genetic basis of dominant early-onset diabetes mellitus in two families. PATIENTS AND METHODS: Molecular analysis by PCR sequencing of the promoter, the 5' untranslated region (UTR) and exons of both GCK and HNF1A genes was carried out in two families with clinically diagnosed dominant diabetes mellitus. RESULTS: The novel HNF1A c.-154_-160TGGGGGT mutation, located in the 5' UTR, was present in several members of the two families in the heterozygous state. Interestingly, the GCK p.Y61X mutation was also identified in three members of one of the families, and two of them carried both mutations in heterozygosis. To the best of our knowledge, this is the first report of the co-inheritance of GCK and HNF1A mutations and the coexistence of maturity-onset diabetes of the young (MODY) 2, MODY 3 and unusual MODY 2-3 genotypes in the same family. CONCLUSIONS: Carriers of both GCK and HNF1A mutations manifested a typical MODY 3 phenotype and showed that the presence of a second mutation in the GCK gene apparently did not modify the clinical outcome, at least at the time of this study. Our data show that co-inheritance of MODY 2 and MODY 3 mutations should be considered, at least in some cases, for accurate genetic testing.

Effect of protein intake and weight gain velocity on body fat mass at 6 months of age: the EU Childhood Obesity Programme.

INTRODUCTION: Higher protein intake during the first year of life is associated with increased weight gain velocity and body mass index (BMI). However, the relationship of protein intake and weight gain velocity with body composition is unclear. OBJECTIVE: To assess if the increases in weight gain velocity and BMI induced by protein intake early in life are related to an increase in fat or fat-free mass. MATERIALS AND METHODS: In all, 41 infants randomized at birth to a higher or lower protein content formula (HP=17 and LP=24, respectively) and 25 breastfed infants were included. Anthropometric measures were assessed at baseline, 6, 12 and 24 months, and fat-free mass (FFM) and fat mass (FM) were assessed by isotope dilution at 6 months. RESULTS: Weight gain velocity (g per month) during the first 6 months of life was significantly higher among HP infants (807.8 (±93.8) vs 724.2 (±110.0) (P=0.015)). Weight gain velocity strongly correlated with FM z-score (r=0.564, P<0.001) but showed no association with FFM z-scores. FFM showed no association with BMI. Nevertheless, FM strongly correlated with BMI at 6, 12 and 24 months (r=0.475, P<0.001; r=0.332, P=0.007 and r=0.247, P=0.051, respectively). FFM and FM z-scores did not differ significantly between HP and LP infants (0.32±1.75 vs -0.31±1.17 and 0.54±2.81 vs -0.02±1.65, respectively). CONCLUSION: Our findings support the hypothesis that higher protein intakes early in life are associated with faster weight gain and in turn to higher adiposity. This mechanism could be a determinant factor for later obesity risk.

Gut microbiota is associated with metabolic health in children with obesity.

BACKGROUND AND AIMS: We aimed to describe and characterize the gut microbiota composition and diversity in children with obesity according to their metabolic health status. METHODS: Anthropometry, Triglycerides, HDL cholesterol, HOMA-IR, and systolic and diastolic blood pressure (SBP, DBP) were evaluated (and z-score calculated) and faecal samples were collected from 191 children with obesity aged from 8 to 14. All children were classified depending on their cardiometabolic status in either a "metabolically healthy" (MHO; n = 106) or "metabolically unhealthy" (MUO; n = 85) group. Differences in gut microbiota taxonomies and diversity between groups (MUO vs MHO) were analysed. Alpha diversity index was calculated as Chao1 and Simpson's index, and ß-diversity was calculated as Adonis Bray-Curtis index. Spearman's correlations and logistic regressions were performed to study the association between cardiometabolic health and the microbiota. RESULTS: Children in the MUO presented significantly lower alpha diversity and richness than those in the MHO group (Chao1 index p = 0.021, Simpson's index p = 0.045, respectively), whereas microbiota ß-diversity did not differ by the cardiometabolic health status (Adonis Bray-Curtis, R2 = 0.006; p = 0.155). The MUO group was characterized by lower relative abundances of the genera Christensenellaceae R7 group (MHO:1.42% [0.21-2.94]; MUO:0.47% [0.02-1.60], p < 0.004), and Akkermansia (MHO:0.26% [0.01-2.19]; MUO:0.01% [0.00-0.36], p < 0.001) and higher relative abundances of Bacteroides (MHO:10.6% [4.64-18.5]; MUO:17.0% [7.18-27.4], p = 0.012) genus. After the adjustment by sex, age, and BMI, higher Akkermansia (OR: 0.86, CI: 0.75-0.97; p = 0.033), Christensenellaceae R7 group (OR: 0.86, 95% CI: 075-0.98; p = 0.031) and Chao1 index (OR: 0.86, CI: 0.96-1.00; p = 0.023) represented a lower risk of the presence of one or more altered cardiovascular risk factors. CONCLUSION: Lower proportions of Christensenellaceae and Akkermansia and lower diversity and richness seem to be indicators of a metabolic unhealthy status in children with obesity.

Insect larvae biofactories as a platform for influenza vaccine production.

Increased production capacity is one of the most important priorities for seasonal and pandemic influenza vaccines. In the present study, we used a baculovirus-insect larvae system (considered small, living biofactories) to improve the production of recombinant influenza virus H1N1 hemagglutinin (HA). Insect larvae produced four-fold more HA protein than insect cells per biomass unit (1 g of fresh larvae weight). A single infected Trichoplusia ni larva produced up to 113 µg of soluble and easily purified recombinant HA, an amount similar to that produced by 1.2×10(8) Sf21 insect cells infected by the same baculovirus. The use of the KDEL endoplasmic reticulum retention signal fused to the HA protein further increased recombinant protein production. Larvae-derived HA was immunogenically functional in vaccinated mice, inducing the generation of hemagglutination inhibition antibodies and a protective immune response against a lethal challenge with a highly virulent virus. The productivity, scalability and cost efficiency of small, living biofactories based on insect larvae suggest a broad-based strategy for the production of recombinant subunit vaccines against seasonal or pandemic influenza as an alternative to fermentation technologies.

Usefulness of high b-value diffusion-weighted MRI in the diagnosis of Creutzfeldt-Jakob disease.

BACKGROUND: current diagnostic criteria of probable Creutzfeldt-Jakob disease (CJD) include a combination of clinical, EEG and analytic data. Recent data indicate that brain MRI including fluid-attenuated inversion recovery (FLAIR) and diffusion-weighted imaging (DWI) sequences can be a valid and reliable tool for the diagnosis of CJD. We describe our experience with high b-value (3000s/mm(2)) diffusion-weighted imaging (DWI) in patients with probable or definite CJD and compare it with standard b-value (1000s/mm(2)) DWI. METHODS: we performed a retrospective analysis of patients admitted to our Hospital Service between 2002 and 2008 with a final diagnosis of probable or definite CJD. Patients were examined using either a 1.5 Tesla or a 3 Tesla MRI. The MRI protocol included T1-weigthed spin-echo sequences, T2-weighted fast spin-echo, FLAIR and DWI sequences with high b-value and standard b-value. RESULTS: during the study period there were 7 patients with probable or definite CJD. Only 3 patients (43%) showed changes on FLAIR sequence consistent with CJD. All the cases were detected with high b-value DWI, including 2 cases (28%) that would have been missed using standard b-value (1000s/mm(2)) DWI. In all the patients the changes were more conspicuous and extensive at high b-value DWI (b=3000s/mm(2)). CONCLUSION: our data indicate that high b-value DWI may improve the sensitivity of brain MRI for the diagnosis of CJD, allowing the detection of some cases that would have been overlooked by conventional sequences.

[Guidelines for specialized nutritional and metabolic support in the critically ill-patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): severe acute pancreatitis]. / Recomendaciones para el soporte nutricional y metabólico especializado del paciente crítico. Actualización. Consenso SEMICYUC-SENPE: pancreatitis aguda grave.

Severe acute pancreatitis (SAP) causes local and systemic complications leading to high catabolic, hypermetabolic and hyperdynamic stress states with marked morbidity and mortality. In the last decade, nutritional support has become a key element in the treatment of SAP. Thus, specialized nutrition is indicated from admission, with enteral nutrition being preferred to parenteral nutrition. Enteral nutrition should be initiated early using infusion through the jejunum beyond the ligament of Treitz to minimize pancreatic stress. There are no specific studies that establish the type of diet to be used but experts recommend the use of polymeric diets. Parenteral nutrition, without a specific formula, is indicated in patients with SAP who are intolerant to enteral nutrition or when the clinical signs of pancreatitis are exacerbated or aggravated by enteral nutrition. Even so, a minimal level of enteral infusion should be maintained to preserve the trophic effect of the intestinal mucosa. In the last few years, several studies of the administration of immunomodulatory diets in patients with SAP have been carried out to demonstrate their effects on the course of the disease. However, there are few clear recommendations on the prognostic benefits of pharmaconutrient enriched diets in these patients. There is substantial scientific evidence suggesting that the only clear indication for pharmaconutrition in patients with SAP is parenteral glutamine administration, which is recommended by all clinical guidelines with distinct grades of evidence.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): neurocritical patient]. / Recomendaciones para el soporte nutricional y metabólico especializado del paciente crítico. Actualización. Consenso SEMICYUC-SENPE: paciente neurocrítico.

Neurocritical patients require specialized nutritional support due to their intense catabolism and prolonged fasting. The preferred route of nutrient administration is the gastrointestinal route, especially the gastric route. Alternatives are the transpyloric route or mixed enteral-parenteral nutrition if an effective nutritional volume of more than 60% cannot be obtained. Total calore intake ranges from 20-30 kcal/kg/day, depending on the period of the clinical course, with protein intake higher than 20% of total calories (hyperproteic diet). Nutritional support should be initiated early. The incidence of gastrointestinal complications is generally higher to other critically-ill patients, the most frequent complication being an increase in gastric residual volume. As in other critically-ill patients, glycemia should be closely monitored and maintained below 150 mg/dL.

[Guidelines for specialized nutritional and metabolic support in the critically-ill patient. Update. Consensus of the Spanish Society of Intensive Care Medicine and Coronary Units-Spanish Society of Parenteral and Enteral Nutrition (SEMICYUC-SENPE): introduction and methodology]. / Recomendaciones para el soporte nutricional y metabólico especializado del paciente crítico. Actualización. Consenso SEMICYUC-SENPE: introducción y metodología.

The Recommendations for Specialized Nutritional Support in Critically-Ill patients were drafted by the Metabolism and Nutrition Working Group of the Spanish Society of Intensive Care Medicine and Coronary Units (SEMICYUC) in 2005. Given the time elapsed since then, these recommendations have been reviewed and updated as a Consensus Document in collaboration with the Spanish Society of Parenteral and Enteral Nutrition (SENPE). The primary aim of these Recommendations was to evaluate the best available scientific evidence for the indications of specialized nutritional and metabolic support in critically-ill patients. The Recommendations have been formulated by an expert panel with broad experience in nutritional and metabolic support in critically-ill patients and were drafted between October 2009 and March 2011. The studies analyzed encompassed metaanalyses, randomized clinical trials, observational studies, systematic reviews and updates relating to critically-ill adults in MEDLINE from 1966 to 2010, EMBASE reviews from 1991 to 2010 and the Cochrane Database of Systematic Reviews up to 2010. The methodological criteria selected were those established in the Scottish Intercollegiate Guidelines Network and the Agency for Health Care policy and Research, as well as those of the Jadad Quality Scale. Adjustment for the level of evidence and grade of recommendation was performed following the proposal of the GRADE group (Grading of Recommendations Assessment, Development and Evaluation Working Group). Sixteen pathological scenarios were selected and each of them was developed by groups of three experts. A feedback system was established with the five members of the Editorial Committee and with the entire Working Group. All discrepancies were discussed and consensus was reached over several meetings, with special emphasis placed on reviewing the levels of evidence and grades of recommendation. The Editorial Committee made the final adjustments before the document was approved by all the members of the Working Group. Finally, the document was submitted to the Scientific Committees of the two Societies participating in the Consensus for final approval. The present Recommendations aim to serve as a guide for clinicians involved in the management and treatment of critically-ill patients and for any specialists interested in the nutritional treatment of hospitalized patients.

Functional analysis of CYP1B1 mutations and association of heterozygous hypomorphic alleles with primary open-angle glaucoma.

Glaucoma is an inherited complex and heterogeneous disease, and one of the most prevalent causes of definitive blindness in the world. Recent reports have indicated that heterozygous mutations of the CYTOCHOROME P4501B1 (CYP1B1) gene are present in 4-10% of patients with primary open-angle glaucoma (POAG). To further evaluate the role of CYP1B1 mutations in POAG we extended our previous association study and carried out a functional analysis of the mutations identified by polymerase chain reaction (PCR) DNA sequencing of the three exons of the gene in a total of 245 unrelated Spanish patients and 326 control subjects. Eight of nine different mutations identified in these patients were cloned and functionally assessed by measuring ethoxyresorufin O-deethylation activity and CYP1B1 stability in transiently transfected HEK-293T cells. All these mutants showed reduced catalytic activity, ranging from 20% to 60% of wild-type and/or decreased protein stability and, therefore, they were classified as hypomorphic alleles. No null alleles were identified in these patients. We found heterozygous hypomorphic CYP1B1 mutations in 17 (6.7%) patients and in seven controls (2.1%) showing that these mutations are associated with an increased risk of POAG (p = 0.005; odds ratio = 3.2; 95% confidence interval = 1.30-9.19). Our data suggest that hypomorphic CYP1B1 mutations are, to date, the main known genetic risk factor in POAG.

A continuous spectrophotometric assay for determination of the aureusidin synthase activity of tyrosinase.

INTRODUCTION: Aurones (aureusidin glycosides) are plant flavonoids that provide yellow colour to the flowers of some ornamental plants. In this study we analyse the capacity of tyrosinase to catalyse the synthesis of aureusidin by tyrosinase from the chalcone THC (2',4',6',4-tetrahydroxychalcone). OBJECTIVE: To develop a simple continuous spectrophotometric assay for the analysis of the spectrophotometric and kinetic characteristics of THC oxidation by tyrosinase. METHODOLOGY: THC oxidation was routinely assayed by measuring the increase in absorbance at 415 nm vs. reaction time. RESULTS: According to the mechanism proposed for tyrosinase, the enzymatic reaction involves the o-hydroxylation of the monophenol THC to the o-diphenol (PHC, 2',4',6',3,4 - pentahydroxychalcone), which is then oxidised to the corresponding o-quinone in a second enzymatic step. This product is highly unstable and thus undergoes a series of fast chemical reactions to produce aureusidin. In these experimental conditions, the optimum pH for THC oxidation is 4.5. The progress curves obtained for THC oxidation showed the appearance of a lag period. The following kinetic parameters were also determined: K(m )= 0.12 mM, V(m )= 13 microM/min, V(m)/K(m )= 0.11/min. CONCLUSION: This method has made it possible to analyse the spectrophotometric and kinetic characteristics of THC by tyrosinase. This procedure has the advantages of a short analysis time, straightforward measurement techniques and reproducibility. In addition, it also allows the study of tyrosinase inhibitors, such as tropolone.

Primary congenital glaucoma caused by the homozygous F261L CYP1B1 mutation and paternal isodisomy of chromosome 2.

Primary congenital glaucoma (PCG), a rare, severe and blinding disease, usually results from mutations in the CYP1B1 gene located in chromosome 2p22.2. Uniparental isodisomy (UPID) is also a rare condition in which a diploid offspring carries two identical copies of a single parental chromosome. By DNA sequence analysis, we found that a proband (female newborn) affected by PCG was homozygous for the null-allele F261L of the CYP1B1 gene. Her father was a heterozygous carrier for this mutation, and unexpectedly her mother carried only the G168D mutation in the heterozygous state. Segregation analysis of eight microsatellite markers which spanned the two arms of chromosome 2 was consistent with paternal isodisomy for this chromosome in the proband. To the best of our knowledge, this is the first reported case of UPID resulting in PCG and the fifth reported case of paternal UPID for chromosome 2. In addition, the absence of a clinical phenotype other than PCG confirms previous observations of there being no paternally imprinted genes in chromosome 2 that have major phenotypic effects. These results, along with previous reports, also suggest that UPID may play a relevant role in recessive diseases linked to chromosome 2.