H. Hipp

Association of galanin haplotypes with alcoholism and anxiety in two ethnically distinct populations.

The neuropeptide galanin (GAL) is widely expressed in the central nervous system. Animal studies have implicated GAL in alcohol abuse and anxiety: chronic ethanol intake increases hypothalamic GAL mRNA; high levels of stress increase GAL release in the central amygdala. The coding sequence of the galanin gene, GAL, is highly conserved and a functional polymorphism has not yet been found. The aim of our study was, for the first time, to identify GAL haplotypes and investigate associations with alcoholism and anxiety. Seven single-nucleotide polymorphisms (SNPs) spanning GAL were genotyped in 65 controls from five populations: US and Finnish Caucasians, African Americans, Plains and Southwestern Indians. A single haplotype block with little evidence of historical recombination was observed for each population. Four tag SNPs were then genotyped in DSM-III-R lifetime alcoholics and nonalcoholics from two population isolates: 514 Finnish Caucasian men and 331 Plains Indian men and women. Tridimensional Personality Questionnaire harm avoidance (HA) scores, a dimensional measure of anxiety, were obtained. There was a haplotype association with alcoholism in both the Finnish (P=0.001) and Plains Indian (P=0.004) men. The SNPs were also significantly associated. Alcoholics were divided into high and low HA groups (⩾ and <mean HA of population). In the Finns, haplotype (P<0.0001) and diplotype (P<0.0001) distributions differed between high HA alcoholics, low HA alcoholics and nonalcoholics. Our results from two independent populations suggest that GAL may contribute to vulnerability to alcoholism, perhaps mediated by dimensional anxiety.

A clinical genetic method to identify mechanisms by which pain causes depression and anxiety

BackgroundPain patients are often depressed and anxious, and benefit less from psychotropic drugs than pain-free patients. We hypothesize that this partial resistance is due to the unique neurochemical contribution to mood by afferent pain projections through the spino-parabrachial-hypothalamic-amygdalar systems and their projections to other mood-mediating systems. New psychotropic drugs for pain patients might target molecules in such brain systems. We propose a method to prioritize molecular targets by studying polymorphic genes in cohorts of patients undergoing surgical procedures associated with a variable pain relief response. We seek molecules that show a significant statistical interaction between (1) the amount of surgical pain relief, and (2) the alleles of the gene, on depression and anxiety during the first postoperative year.ResultsWe collected DNA from 280 patients with sciatica due to a lumbar disc herniation, 162 treated surgically and 118 non-surgically, who had been followed for 10 years in the Maine Lumbar Spine Study, a large, prospective, observational study. In patients whose pain was reduced >25% by surgery, symptoms of depression and anxiety, assessed with the SF-36 Mental Health Scale, improved briskly at the first postoperative measurement. In patients with little or no surgical pain reduction, mood scores stayed about the same on average. There was large inter-individual variability at each level of residual pain. Polymorphisms in three pre-specified pain-mood candidate genes, catechol-O-methyl transferase (COMT), serotonin transporter, and brain-derived neurotrophic factor (BDNF) were not associated with late postoperative mood or with a pain-gene interaction on mood. Although the sample size did not provide enough power to persuasively search through a larger number of genes, an exploratory survey of 25 other genes provides illustrations of pain-gene interactions on postoperative mood – the mu opioid receptor for short-term effects of acute sciatica on mood, and the galanin-2 receptor for effects of unrelieved post-discectomy pain on mood one year after surgery.ConclusionGenomic analysis of longitudinal studies of pain, depression, and anxiety in patients undergoing pain-relieving surgery may help to identify molecules through which pain alters mood. Detection of alleles with modest-sized effects will require larger cohorts.

Alcoholism is associated with GALR3 but not two other galanin receptor genes

The neuropeptide galanin is widely expressed in the periphery and the central nervous system and mediates diverse physiological processes and behaviors including alcohol abuse, depression and anxiety. Four genes encoding galanin and its receptors have been identified (GAL, GALR1, GALR2 and GALR3). Recently we found that GAL haplotypes were associated with alcoholism, raising the possibility that genetic variation in GALR1, GALR2 and GALR3 might also alter alcoholism risk. Tag single nucleotide polymorphisms (SNPs) were identified by genotyping SNP panels in controls from five populations. For the association study with alcoholism, six GALR1, four GALR2 and four GALR3 SNPs were genotyped in a large cohort of Finnish alcoholics and non‐alcoholics. GALR3 showed a significant association with alcoholism that was driven by one SNP (rs3091367). Moreover, the combination of the GALR3 rs3091367 risk allele and GAL risk haplotypes led to a modestly increased odds ratio (OR) for alcoholism (2.4) as compared with the effect of either GAL (1.9) or GALR3 alone (1.4). Likewise, the combination of the GALR3 and GAL risk diplotypes led to an increased OR for alcoholism (4.6) as compared with the effect of either GAL (2.0) or GALR3 alone (1.6). There was no effect of GALR1 or GALR2 on alcoholism risk. This evidence suggests that GALR3 mediates the alcoholism‐related actions of galanin.

Haplotype-based analysis of alpha 2A, 2B, and 2C adrenergic receptor genes captures information on common functional loci at each gene.

AbstractThe alpha 2-adrenergic receptors (α2-AR) mediate physiological effects of epinephrine and norepinephrine. Three genes encode α2-AR subtypes carrying common functional polymorphisms (ADRA2A Asn251Lys, ADRA2B Ins/Del301-303 and ADRA2C Ins/Del322-325). We genotyped these functional markers plus a panel of single nucleotide polymorphisms evenly spaced over the gene regions to identify gene haplotype block structure. A total of 24 markers were genotyped in 96 Caucasians and 96 African Americans. ADRA2A and ADRA2B each had a single haplotype block at least 11 and 16 kb in size, respectively, in both populations. ADRA2C had one haplotype block of 10 kb in Caucasians only. For the three genes, haplotype diversity and the number of common haplotypes were highest in African Americans, but a similar number of markers (3–6) per block was sufficient to capture maximum diversity in either population. For each of the three genes, the haplotype was capable of capturing the information content of the known functional locus even when that locus was not genotyped. The α2-AR haplotype maps and marker panels are useful tools for genetic linkage studies to detect effects of known and unknown α2-AR functional loci.

Haplotype structure of the beta adrenergic receptor genes in US Caucasians and African Americans

The beta-adrenergic receptors (β-AR) are G protein-coupled receptors activated by epinephrine and norepinephrine and are involved in a variety of their physiological functions. Previously, three β-AR genes (ADRB1, ADRB2 and ADRB3) were resequenced, identifying polymorphisms that were used in genetic association studies of cardiovascular and metabolic disorders. These studies have produced intriguing but inconsistent results, potentially because the known functional variants: ADRB1 Arg389Gly and Gly49Ser, ADRB2 Arg16Gly and Gln27Glu, and ADRB3 Arg64Trp provided an incomplete picture of the total functional diversity at these genes. Therefore, we created marker panels for each β-AR gene that included the known functional markers and also other markers evenly spaced and with sufficient density to identify haplotype block structure and to maximize haplotype diversity. A total of 27 markers were genotyped in 96 US Caucasians and 96 African Americans. In both populations and for each gene, a single block with little evidence of historical recombination was observed. For each gene, haplotype captured most of the information content of each functional locus, even if that locus was not genotyped, and presumably haplotype would capture the signal from unknown functional loci whose alleles are of moderate abundance. This study demonstrates the utility of using β-AR gene haplotype maps and marker panels as tools for linkage studies on β-AR function.

Haplotype block and superblock structures of the alpha1-adrenergic receptor genes reveal echoes from the chromosomal past

A significant proportion of the human genome is contained within haplotype blocks across which pairwise linkage disequilibrium (LD) is very high. However, LD is also often high between markers at more remote distances, and within different haplotype blocks. Here, we evaluate the origins of haplotype block structure in the three genes for alpha1 adrenergic receptors (alpha1-AR) in the human genome ( ADRA1A, ADRA1B and ADRA1D) by genotyping dense single-nucleotide polymorphism (SNP) marker maps, and show that LD signals between distant markers are due to the presence of extended haplotype superblocks in individuals with ancient chromosomes which have escaped historic recombination. ARs mediate the physiological effects of epinephrine and norepinephrine, and are targets of many therapeutic drugs. This work has identified haplotype backgrounds of alpha1-AR missense variants, haplotype block structures in US Caucasians and African Americans, and haplotype tag SNPs for each block, and we present strong evidence for ancient haplotype block superstructure at these genes which has been partially disrupted by recombination, and evidence for reinstatement of linkage disequilibrium by subsequent recombination events. ADRA1A is comprised of four haplotype blocks in US Caucasians, while in African Americans Block 1 is split. ADRA1B has four blocks in US Caucasians, but in African Americans only the first two blocks are present. ADRA1D has two blocks in US Caucasians, and the first block is replaced by two smaller blocks in African Americans. For both ADRA1A and ADRA1B, haplotype superstructures may represent a novel, higher-level hierarchy in the human genome, which may reduce redundancy of testing by further aggregation of genotype data.

Reproductive and gynecologic care of women with fragile X primary ovarian insufficiency (FXPOI).

Objective:Approximately 20% of women with a premutation in the FMR1 gene experience primary ovarian insufficiency (POI). We explored diagnostic patterns, frequency of appropriate hormone replacement, obstetric outcomes, fertility treatment, reproductive decisions, and counseling of women with fragile X-associated POI (FXPOI). Methods:Semistructured interviews with 79 women with FXPOI were conducted by a single interviewer. FMR1 cytosine-guanine-guanine repeat size was determined from a blood, saliva, or buccal sample. Results:The median age of POI onset for women in our study was 33 years. Seventy-two percent of the women had an FMR1 cytosine-guanine-guanine repeat length of 80 to 100. Mean length of time from symptom onset to POI diagnosis was 1.12 years, longer in women with a younger age of POI onset and shorter in women who knew they were carriers. After diagnosis, 52% of women never took hormone therapy, started it years after POI diagnosis, or stopped it before 45 years of age. Forty-nine percent of the women had infertility, but 75% had had at least one genetically related child. Obstetric outcomes were similar to the general population. Forty-six percent of women had a diagnosis of low bone mineral density or osteoporosis, and an additional 19% had never had a bone density assessment. Conclusions:Women with FXPOI are at significant risk for delayed POI diagnosis and undertreatment with hormone therapy. Although approximately 50% of women had infertility, most were able to conceive at least one child and had no elevated risk of adverse obstetric outcomes.

First trimester pregnancy loss after fresh and frozen in vitro fertilization cycles

OBJECTIVE To characterize risks for early pregnancy loss after fresh and frozen IVF cycles and to investigate whether risk is modified by infertility diagnoses or transfer of embryos in fresh versus frozen cycles. DESIGN Retrospective cohort study using data from the National Assisted Reproductive Technology (ART) Surveillance System. SETTING Fertility centers. PATIENT(S) Clinical pregnancies achieved with fresh and frozen IVF cycles between 2007 and 2012 (N = 249,630). INTERVENTION(S) None. MAIN OUTCOME MEASURE(S) First trimester pregnancy loss. RESULT(S) A diagnosis of uterine factor was associated with an increased risk of loss in women aged 40 years and younger (<30 years: adjusted risk ratio (aRR) = 1.24, 95% confidence interval (CI) 1.04-1.48; 30-34 years: aRR = 1.27, 95% CI 1.17-1.38; 35-37 years: aRR = 1.12, 95% CI 1.03-1.21; 38-40 years: aRR = 1.08, 95% CI 1.01-1.17). There was an increased risk of loss in women with diminished ovarian reserve aged 30-34 years (aRR = 1.08, 95% CI 1.01-1.15) and in women with ovulatory dysfunction younger than 35 years (<30 years: aRR = 1.12, 95% CI 1.05-1.19; 30-34 years: aRR = 1.07, 95% CI 1.02-1.13). There was an increased risk of loss after frozen ETs versus fresh among women younger than 38 years, but this remained significant in the subanalysis of similar quality embryos only in women younger than 30 years (aRR = 1.16, 95% CI 1.04-1.32). CONCLUSION(S) Uterine factor had the largest increased risk of loss among infertility diagnoses, although the magnitudes of all risks were small. When transferring embryos of similar quality, the risks of loss were similar between fresh and frozen cycles.

Haplotype architecture of the norepinephrine transporter gene SLC6A2 in four populations

AbstractThe norepinephrine transporter (NET) regulates levels of monoamine neurotransmitters integral to a variety of behaviors and autonomic functions. Two SLC6A2 polymorphisms have been used in genetic association studies, generating intriguing but nondefinitive results on traits such as hypertension and mood. One of these SLC6A2 variants is functional but rare. The other is common but not informative over the entire 48 kb SLC6A2 region and is insufficient to capture the functional diversity potentially contained within any SLC6A2 region. To elucidate SLC6A2 haplotype structure and define markers sufficient to capture haplotype diversity within detected haplotype blocks, 26 single-nucleotide polymorphisms (SNPs) were genotyped in 384 individuals evenly divided across Finnish Caucasian, US Caucasian, Plains American Indian, and African American populations. Three conserved blocks, 13.6, 12.5, and 25 kb in size and showing little evidence for historical recombination were observed in all populations. Haplotype diversity in block 1 and numbers of common haplotypes were highest in African Americans, among whom 5-6 optimal markers were sufficient to maximize diversity of each block. For other populations, 2-3 markers/block sufficed, but the optimal markers differed across populations. The SLC6A2 haplotype map and 25-marker panel (excluding the monomorphic one) is a comprehensive tool for genetic linkage studies on phenotypes related to NET function.

Assisted reproductive technology with donor sperm: national trends and perinatal outcomes

BACKGROUND: Information regarding the use of donor sperm in assisted reproductive technology, as well as subsequent treatment and perinatal outcomes, remains limited. Outcome data would aid patient counseling and clinical decision making. OBJECTIVES: The objectives of the study were to report national trends in donor sperm utilization and live birth rates of donor sperm–assisted reproductive technology cycles in the United States and to compare assisted reproductive technology treatment and perinatal outcomes between cycles using donor and nondonor sperm. We hypothesize these outcomes to be comparable between donor and nondonor sperm cycles. STUDY DESIGN: This was a retrospective cohort study using data from all US fertility centers reporting to the Centers for Disease Control and Preventions National Assisted Reproductive Technology Surveillance System, accounting for ˜98% of assisted reproductive technology cycles (definition excludes intrauterine insemination). The number and percentage of assisted reproductive technology cycles using donor sperm and rates of pregnancy, live birth, preterm birth (<37 weeks), and low birthweight (<2500 g) were the primary outcomes measured. Treatments assessed include use of donor vs nondonor sperm. The trends analysis included all banking and fresh assisted reproductive technology cycles using donor and autologous oocytes performed between 1996 and 2014 (n = 1,710,034). The outcomes analysis was restricted to include only fresh autologous cycles performed between 2010 and 2014 (n = 437,569) to focus on cycles with a potential outcome and cycles reflective of current practice, thereby improving the clinical relevance. Cycles canceled prior to retrieval were excluded. Statistical analysis included linear regression to explore polynomial trends and log‐binomial regression to estimate relative risk for outcomes among cycles using donor and nondonor sperm. RESULTS: Of all banking and fresh donor and autologous oocyte assisted reproductive technology cycles performed between 1996 and 2014, 74,892 (4.4%) used donor sperm. In 2014, 7351 assisted reproductive technology cycles using donor sperm were performed, as compared with 1763 in 1996 (6.2% vs 3.8% of all cycles). Among all autologous oocyte cycles performed between 2010 and 2014, the live birth rate was lower for donor sperm (27.9%) than nondonor sperm cycles (32.5%); however, after adjustment for maternal age, donor sperm use was associated with an increased likelihood of live birth (adjusted relative risk, 1.06, 95% confidence interval, 1.01–1.10). Per transfer, there was no significant difference in live birth rates for donor vs nondonor sperm (31.9% vs 36.8%; adjusted relative risk, 1.04, 95% confidence interval, 0.998–1.09). Per singleton live birth, there was no significant difference in preterm birth (11.5% vs 11.8%; adjusted relative risk, 0.98, 95% confidence interval, 0.90–1.06); however, low birthweight delivery was slightly lower in donor sperm cycles (8.8% vs 9.4%; adjusted relative risk, 0.91, 95% confidence interval, 0.83–0.99). CONCLUSION: Donor sperm use in assisted reproductive technology has increased in the United States, accounting for approximately 6% of all assisted reproductive technology cycles in 2014. Assisted reproductive technology treatment and perinatal outcomes were clinically similar in donor and nondonor sperm cycles.