Male infant with paternal uniparental diploidy mosaicism and a 46,XX/46,XY karyotype.

A male patient with mosaic paternal uniparental diploidy (PUD) is presented. After birth, the patient presented with hypoglycemia, hemihypertrophy, umbilical hernia, and hepatomegaly. Afterward pancreatic hypertrophy, liver hemangiomas, and cysts were detected sonographically. At the age of 3.5 months, hepatoblastoma was diagnosed. To investigate suspected Beckwith-Wiedemann syndrome (BWS), extensive genetic analyses were performed using DNA from chorionic villus sampling, amniocentesis, and peripheral blood lymphocytes (chromosome analysis, methylation-specific multiplex ligation-dependent probe amplification assays, microsatellite analyses, and single nucleotide polymorphism array analysis). These analyses led to the detection of mosaic PUD. In peripheral blood lymphocytes, a male cell line (46,XY[27]/46,XX[5]) predominated, suggesting a mixture of uniparental isodisomy and heterodisomy. The genetic analyses suggest that the mosaic PUD status was attributable to fertilization of an oocyte by two sperms, with subsequent triploidy rescue giving rise to haploidy, which in turn was rescued. Notably, in the majority of the 28 mosaic PUD patients reported to date, BWS was initially suspected. Mosaic PUD status is associated with a higher risk for a broad range of malignant and benign tumors than in BWS. As tumors can also occur after childhood surveillance into adolescence is indicated. Mosaic PUD must therefore be considered in patients with suspected BWS.

Postnatal nutrition in extremely low birth weight infants and its impact on growth until the age of 6 years.

AIM: To examine the impact of postnatal nutrition on long-term growth in extremely low birth weight infants. METHOD: Retrospective analysis of postnatal nutrition and observational study of growth in 52 ELBW infants until the age of six. RESULTS: Changes (Δ) in weight and length standard deviation scores (SDS) between birth to term correlated with protein intake (r(w) = 0.36; p = 0.009; r(L) = 0.35; p = 0.01), whereas ΔHC correlated with lipid intake (r(HC) = 0.38; p = 0.005). Analysis of various intervals (0-2, 3-5, 6-8 and 9-11 weeks) only showed significant impact on growth for energy (r = 0.3; p < 0.05) and lipids (r = 0.23; p < 0.05) at 6-8 weeks. No significant correlations were found between postnatal nutritional parameters and long-term growth. However, postnatal growth restraint was negatively associated with length SDS (r = -0.34; p = 0.015) and body mass index SDS (r = -0.34; p = 0.018) at the age of six. Infants with postnatal growth restraint (n = 25) caught up more in length (+1.78 SDS) than in weight (+0.43 SDS), whereas small for gestational age infants (n = 8) caught up more in weight (+1.35 SDS) than in length (+1.07 SDS). This difference remained significant at the age of six. CONCLUSION: Although no direct association between postnatal nutrition and long-term growth was found, weight at discharge was a strong predictor for long-term growth.

Association of COMT genotypes with S-COMT promoter methylation in growth-discordant monozygotic twins and healthy adults.

BACKGROUND: Catechol-O-Methyltransferase (COMT) plays a key role in dopamine and estrogen metabolism. Recently, COMT haplotypes rather than the single polymorphism Val158Met have been reported to underlie differences in protein expression by modulating mRNA secondary structure. So far, studies investigating the epigenetic variability of the S-COMT (soluble COMT) promoter region mainly focused on phenotypical aspects, and results have been controversial. METHODS: We assessed S-COMT promoter methylation in saliva and blood derived DNA with regard to early pre- and postnatal growth as well as to genotype for polymorphisms rs6269, rs4633, and rs4680 (Val158Met) in 20 monozygotic twin pairs (mean age 4 years), who were discordant for intrauterine development due to severe feto-fetal-transfusion syndrome. Methylation levels of two previously reported partially methylated cytosines were determined by the quantitative SIRPH (SNuPE- IP RP HPLC) assay. RESULTS: Overall, we observed a high variability of S-COMT promoter methylation, which did not correlate with individual differences in the pre- or postnatal growth pattern. Within the twin pairs however we noted a distinct similarity that could be linked to underlying COMT genotypes. This association was subsequently confirmed in a cohort of 93 unrelated adult controls. Interestingly, 158Val-alleles were found at both ends of the epigenotypical range, which is in accordance with a recently proposed model of COMT haplotypes corresponding to a continuum of phenotypical variability. CONCLUSION: The strong heritable component of S-COMT promoter methylation found in our study needs to be considered in future approaches that focus on interactions between COMT epigenotype and phenotype.

Bone maturation in extremely low birth weight infants in relation to birth weight and endocrine parameters.

Modern intensive care techniques have led to higher survival rates of extremely low birth weight infants (ELBW, birth weight <1,000 g). Previous studies have suggested a link between abnormal birth parameters and subsequent endocrine disturbances, but a possible impact on bone maturation during childhood has not been studied. ELBW children were studied (mean chronological age (CA), 6.01 years; range, 4.5-8.2). Skeletal maturation was assessed according to Greulich and Pyle (8). Bone age (BA) was defined as retarded when DeltaBA-CA was < -1 SD and accelerated when DeltaBA-CA was >+1 SD. BA was either retarded or accelerated in 15 patients (24.6%). Twenty-one of 61 radiograms (34.4%) showed a discordant BA with a marked gender difference (14/24 boys; 7/37 girls). DeltaBA-CA correlated significantly with BMI (r = 0.36; p = 0.005) and height SDS (r = 0.35; p = 0.006). We found significant correlations between BA and androgens. Insulin-like growth factor binding protein-1 (IGFBP-1), which decreases in insulin-resistant individuals, correlated negatively with BA. In conclusion, bone maturation in ELBW children is correlative with height and weight. It is modulated by a variety of metabolic factors, including IGFBP-1 and androgens. Bone age, together with height and weight catch-up, can thus possibly serve as early indicators of insulin resistance later in life.

Does gender-specific BMI development modulate insulin sensitivity in extremely low birth weight infants?

BACKGROUND: Increasing numbers of extremely low birth weight infants (ELBW, birth weight < 1,000 g) survive. We studied the impact of birth weight, gender, and catch-up growth on metabolic parameters in ELBW infants. CHILDREN: Sixty-three ELBW children were investigated at a mean age of 5.8 years. Forty-eight showed catch-up growth. RESULTS: ELBW children who were small for gestational age were significantly shorter than those whose size was appropriate for their gestational age (height SDS: -1.1 [SD 0.8] vs -0.4 [0.9]; p < 0.001). This corresponded with significantly lower standard deviation scores for IGF-I (-1.1 [1.3] vs 0.1 [0.8]; p < 0.05) and IGFBP-3 (-0.7 [1.7] vs 0.4 [1.1]; p < 0.05). No differences were found regarding fasting insulin, glucose, HOMA and IGFBP-1. The catch-up group showed lower IGFBP-1 concentrations than the non-catch-up group. IGFBP-1 decreased in individuals who became more insulin resistant. No differences were found regarding mean IGF-1 and IGFBP-3 SDS. A gender-related pattern was found for weight development: girls demonstrated a normalization of BMI from the age of 2 years whereas boys remained at a mean BMI of -1.96 SDS. Corresponding to this, girls showed lower IGFBP-1 levels than boys. CONCLUSION: Metabolic parameters in ELBW children are modulated by subsequent catch-up growth and sex-dependent weight development, resulting in measurable differences even in early childhood.

Association of the growth hormone receptor d3-variant and catch-up growth of preterm infants with birth weight of less than 1500 grams.

BACKGROUND: Preterm infants with very low birth weight frequently exhibit impaired longitudinal growth during the first years of life. Recently, the d3-isoform (genomic deletion of exon 3) of the GH receptor (GHR) has been linked to an increased responsiveness to GH. OBJECTIVE: Our objective was to test whether the GHRd3 isoform is associated with postnatal catch-up growth in very low birth weight preterm infants. DESIGN AND PATIENTS: We compared the postnatal growth pattern of 77 otherwise healthy preterm infants (mean gestational age, 28.5 wk; range, 23-35 wk) with a birth weight below 1500 g (mean birth weight, 941 g) to their GHR exon 3 genotype, which was analyzed by multiplex PCR. On examination, mean age of the children was 6.0 yr (range, 4.2-8.0 yr). RESULTS: Children homozygous or heterozygous for the GHRd3 allele showed a significantly higher rate of postnatal catch-up, compared with those homozygous for the full-length allele. CONCLUSIONS: Our results define the GHR exon 3 genotype as a predictor for the postnatal growth pattern of very low birth weight preterm infants. Those who carry at least one GHRd3 allele are more likely to catch-up.

Impact of Early Nutrition on Body Composition in Children Aged 9.5 Years Born with Extremely Low Birth Weight.

To evaluate body composition, metabolism and growth as well as their interaction with early nutrition in former extremely low birth weight infants (ELBW), we assessed qualitative and quantitative nutritional intake during initial hospitalization and infantile growth parameters in 61 former ELBW infants with a birth weight <1000 g. In two follow-up exams, physical and biochemical development were measured at 5.7 and at 9.5 years. At the second follow-up, in addition to biochemical reassessment, body composition was analyzed by dual-energy x-ray absorptiometry (DEXA). Protein intake between birth and discharge was associated with weight gain in the first six months of life (r = 0.51; p < 0.01). Weight catch-up preceded height catch-up. Protein intake in early infancy correlated highly significantly with abdominal fat mass (r = 0.49; p < 0.05), but not with lean body mass at 9.5 years (r = 0.30; not significant (n.s.). In contrast to nutrient intake, birth weight was associated with lean body mass (r = 0.433; p < 0.001). Early protein and carbohydrate intake were associated with high-density lipoprotein (HDL)-cholesterol, and early catch-up growth correlated with fasting insulin at follow-up. Stepwise linear regression demonstrated that protein intake predicted fat mass (p < 0.05), whereas only gender and birth weight standard deviation score (SDS) contributed significantly to lean body mass variation (p < 0.05). Our results suggest an important impact of early nutrient intake on body composition and metabolism in later childhood in ELBW children.

Increased Steroid Excretion in Children with Extremely Low Birth Weight at a Median Age of 9.8 years.

BACKGROUND: Events during foetal or early extrauterine life may affect bodily structure and/or functions and even pave the way for adult diseases. AIMS: To find whether extremely low birth weight (ELBW) infants differ from healthy controls regarding the excretion of steroid metabolites. METHODS: The study compared 17 female and 10 male ELBW infants, all prepubertal, aged 8-11 years, birth weight <1,000 g, with 27 age- and sex-matched controls. All were healthy at the time of the study. Height, weight and BMI did not differ between the groups. Results were adjusted according to body surface area. 36 urinary steroid metabolites were quantified by gas chromatography-mass spectrometry. RESULTS: In the ELBW girls 33/36 steroid metabolites were higher (19 significantly) than in the controls. All 36 steroid metabolites were higher in the ELBW boys (9 significantly) than in the controls. Sums of mineralocorticoid precursors, metabolites descriptive for cortisol and parameters of adrenal androgen production were significantly higher in ELBW infants (both sexes). Only the sum of the metabolites known to be illustrative for adrenal 11ß-hydroxysteroid dehydrogenase activity was not different. CONCLUSION: Prepubertal ELBW children have an augmented urinary excretion of adrenal androgens, cortisol and mineralocorticoid precursors. These findings corroborate and help to explain the link between early-life adversity and subsequent adrenocortical function.

11p15 DNA-methylation analysis in monozygotic twins with discordant intrauterine development due to severe twin-to-twin transfusion syndrome.

BACKGROUND: Prenatal growth restriction and low birth weight have been linked to long-term alterations of health, presumably via adaptive modifications of the epigenome. Recent studies indicate a plasticity of the 11p15 epigenotype in response to environmental changes during early stages of human development. STUDY DESIGN: We analyzed methylation levels at different 11p15 loci in 20 growth-discordant monozygotic twin pairs. Intrauterine development was discordant due to severe twin-to-twin transfusion syndrome (TTTS), which was treated by fetoscopic laser coagulation of communicating vessels before 25 weeks of gestation. Methylation levels at age 4 were determined in blood and buccal cell-derived DNA by the single nucleotide primer extension reaction ion pair reverse-phase high performance liquid chromatography (SNuPE IP RP HPLC) assay. Methylation at LINE-1 repeats was analyzed as an estimate of global methylation. RESULTS: In general, variance of locus-specific methylation levels appeared to be higher in buccal cell- as compared to blood cell-derived DNA samples. Paired analyses within the twin pairs revealed significant differences at only one CpG site (IGF2 dmr0 SN3 (blood), +1.9% in donors; P = 0.013). When plotting the twin pair-discordance in birth weight against the degree of discordance in site-specific methylation at age 4, only a few CpGs were found to interact (one CpG site each at IGF2dmr0 in blood/saliva DNA, one CpG at LINE-1 repeats in saliva DNA), with 26 to 36% of the intra-twin pair divergence at these sites explained by prenatal growth discordance. However, across the entire cohort of 40 children, site-specific methylation did not correlate with SD-scores for weight or length at birth. Insulin-like growth factor-II serum concentrations showed significant within-twin pair correlations at birth (R = 0.57) and at age 4 (R = 0.79), but did not differ between donors and recipients. They also did not correlate with the analyzed 11p15 methylation parameters. CONCLUSION: In a cohort of 20 growth-discordant monozygotic twin pairs, severe alteration in placental blood supply due to TTTS appears to leave only weak, if any, epigenetic marks at the analyzed CpG sites at 11p15.

Growth hormone receptor d3-variant, insulin-like growth factor binding protein-1 -575G/A polymorphism and postnatal catch-up growth: association with parameters of glucose homeostasis in former extremely low birth weight preterm infants.

BACKGROUND: Low birth weight predisposes to the development of insulin resistance. In addition to auxological parameters such as rapid catch-up growth, low IGFBP-1 serum levels in childhood have been linked to an increased risk of insulin resistance later in life. Concerning postnatal growth, we previously reported the GHRd3-variant to be associated with catch-up growth in preterm infants. In children born small for gestational age, a common IGFBP-1 promoter polymorphism -575G/A has been linked to IGFBP-1 serum levels and has been suggested to be an additional player in the interaction between the IGF-IGFBP-axis and metabolism. STUDY DESIGN: We analyzed postnatal growth, metabolic parameters, and genotypes for the GHRd3-variant and IGFBP-1 -575G/A in 51 former extremely low birth weight preterm infants (mean age 5.9 years). RESULTS: GHRd3 but not IGFBP-1 -575G/A was significantly associated with postnatal growth velocity. Catch-up growth, GHRd3, and IFGBP-1 -575G/A did not influence fasting insulin or HOMA-IR. However, we found significantly higher HbA1c and lower IGFBP-1 concentrations in GHRd3-carriers, a finding not seen with respect to IGFBP-1 -575G/A. Interestingly, HbA1c and IGFBP-1 levels also did not differ between children either with or without catch-up growth. CONCLUSIONS: In addition to an association with catch-up growth, GHR exon 3 genotype significantly modulates HbA1c and IGFBP-1 concentrations in former ELBW infants. In order to confirm this observation and to clarify whether the GHRd3-variant might be considered as an independent modulator of the low birth weight infant's risk to develop insulin resistance later in life, larger studies extending to later ages are required.