Characterization of the human jumonji gene

A Functional Single Nucleotide Polymorphism in the 3' Untranslated Region of the Porcine JARID2 Gene Is Associated with Aggressive Behavior of Weaned Pigs after Mixing

In pig production, pigs often show more aggressive behavior after mixing, which adversely affects animal welfare and growth performance. The Jumonji and structural domain-rich AT interaction domain 2 (JARID2) gene plays an important role in neurodevelopment in mice and various psychiatric disorders in humans. The JARID2 gene may impact the aggressive behavior of pigs. By observing the behavior of 500 weaned pigs during the first 72 h after mixing, the ear tissue samples of the 12 most aggressive and 12 least aggressive pigs were selected for DNA resequencing based on the intensity of their aggressive behavior. Large group correlation analysis indicated that the rs3262221458 site located in the 3'-UTR region of the porcine JARID2 gene has a strong relationship with the aggressive behavior of weaned pigs. Pigs with the mutant TT genotype of rs3262221458 have more aggressive behavior than those pigs with the GG and GT genotypes. The dual luciferase assay indicated that the luciferase activity of the plasmids containing the G allele of rs326221458 was significantly less than that of plasmids containing the T allele of rs326221458 and control groups. The binding ability of miR-9828-3p to sequences containing the T allele was less than that of sequences containing the G allele. The overexpression of miR-9828-3p in porcine neuroglial cells (PNGCs) and PK15 cells significantly decreased the mRNA and protein levels of the JARID2 gene. In addition, miR-9828-3p inhibited the proliferation of PNGCs. After inhibiting miR-9828-3p, the mRNA and protein expression levels of JARID2 increased, and the proliferation of PNGCs showed an opposite trend to the cells that forced the expression of miR-9828-3p. In addition, interference with the JARID2 gene by siRNA can effectively inhibit the proliferation of PNGCs. In summary, we found that the rs326221458 locus regulates the expression of the JARID2 gene by affecting the binding of miR-9828-3p and the JARID2 gene, thereby affecting the aggressive behavior of weaned pigs after mixing.

Molecular Cloning and Expression Responses of Jarid2b to High-Temperature Treatment in Nile Tilapia (Oreochromis niloticus)

Nile tilapia is a GSD + TE (Genetic Sex Determination + Temperature Effect) fish, and high-temperature treatment during critical thermosensitive periods (TSP) can induce the sex reversal of Nile tilapia genetic females, and brain transcriptomes have revealed the upregulation of Jarid2 (Jumonji and AT-rich domain containing 2) expression after 36 °C high-temperature treatment for 12 days during TSP. It was shown that JARID2 forms a complex with polycomb repressive complex 2 (PRC2) that catalyzed H3K27me3, which was strongly associated with transcriptional repression. In this study, Jarid2b was cloned and characterized in Nile tilapia, which was highly conserved among the analyzed fish species. The expression of Jarid2b was upregulated in the gonad of 21 dpf XX genetic females after 12-day high-temperature treatment and reached a similar level to that of males. Similar responses to high-temperature treatment also appeared in the brain, heart, liver, muscle, eye, and skin tissues. Interestingly, Jarid2b expression was only in response to high-temperature treatment, and not to 17α-methyltestosterone (MT) or letrozole treatments; although, these treatments can also induce the sex reversal of genetic Nile tilapia females. Further studies revealed that Jarid2b responded rapidly at the 8th hour after high-temperature treatment. Considering that JARID2 can recruit PRC2 and establish H3K27me3, we speculated that it might be an upstream gene participating in the regulation of Nile tilapia GSD + TE through regulating the H3K27 methylation level at the locus of many sex differentiation-related genes.

A novel partial de novo duplication of JARID2 gene causing a neurodevelopmental phenotype

BACKGROUND

Deletions covering the entire or partial JARID2 gene as well as pathogenic single nucleotide variants leading to haploinsufficiency of JARID2 have recently been shown to cause a clinically distinct neurodevelopmental syndrome. Here, we present a previously undescribed partial de novo duplication of the JARID2 gene in a patient displaying features similar to those of patients with JARID2 loss-of-function variants.

CASE REPORT

The index patient presents with abnormalities in gross motor skills and speech development as well as neuropsychiatric disorders. The patient has markedly dark infraorbital circles and slightly prominent supraorbital ridges.Whole-genome sequencing and array comparative genomic hybridization revealed a novel disease-causing variant type, a partial tandem duplication of JARID2, covering the exons 1-7. Furthermore, RNA sequencing validated the increased expression of these exons. Expression alterations were also detected in target genes of the PRC2 complex, in which JARID2 acts as an essential member.

CONCLUSION

Our data add to the variety of different pathogenic variants associated with JARID2 neurodevelopmental syndrome.

DNA binding by polycomb-group proteins: searching for the link to CpG islands

Polycomb group proteins predominantly exist in polycomb repressive complexes (PRCs) that cooperate to maintain the repressed state of thousands of cell-type-specific genes. Targeting PRCs to the correct sites in chromatin is essential for their function. However, the mechanisms by which PRCs are recruited to their target genes in mammals are multifactorial and complex. Here we review DNA binding by polycomb group proteins. There is strong evidence that the DNA-binding subunits of PRCs and their DNA-binding activities are required for chromatin binding and CpG targeting in cells. In vitro, CpG-specific binding was observed for truncated proteins externally to the context of their PRCs. Yet, the mere DNA sequence cannot fully explain the subset of CpG islands that are targeted by PRCs in any given cell type. At this time we find very little structural and biophysical evidence to support a model where sequence-specific DNA-binding activity is required or sufficient for the targeting of CpG-dinucleotide sequences by polycomb group proteins while they are within the context of their respective PRCs, either PRC1 or PRC2. We discuss the current knowledge and open questions on how the DNA-binding activities of polycomb group proteins facilitate the targeting of PRCs to chromatin.

A Structural Perspective on Gene Repression by Polycomb Repressive Complex 2

Polycomb Repressive Complex 2 (PRC2) is a major repressive chromatin complex formed by the Polycomb Group (PcG) proteins. PRC2 mediates trimethylation of histone H3 lysine 27 (H3K27me3), a hallmark of gene silencing. PRC2 is a key regulator of development, impacting many fundamental biological processes, like stem cell differentiation in mammals and vernalization in plants. Misregulation of PRC2 function is linked to a variety of human cancers and developmental disorders. In correlation with its diverse roles in development, PRC2 displays a high degree of compositional complexity and plasticity. Structural biology research over the past decade has shed light on the molecular mechanisms of the assembly, catalysis, allosteric activation, autoinhibition, chemical inhibition, dimerization and chromatin targeting of various developmentally regulated PRC2 complexes. In addition to these aspects, structure-function analysis is also discussed in connection with disease data in this chapter.

JARID2 haploinsufficiency is associated with a clinically distinct neurodevelopmental syndrome

PURPOSE

JARID2, located on chromosome 6p22.3, is a regulator of histone methyltransferase complexes that is expressed in human neurons. So far, 13 individuals sharing clinical features including intellectual disability (ID) were reported with de novo heterozygous deletions in 6p22-p24 encompassing the full length JARID2 gene (OMIM 601594). However, all published individuals to date have a deletion of at least one other adjoining gene, making it difficult to determine if JARID2 is the critical gene responsible for the shared features. We aim to confirm JARID2 as a human disease gene and further elucidate the associated clinical phenotype.

METHODS

Chromosome microarray analysis, exome sequencing, and an online matching platform (GeneMatcher) were used to identify individuals with single-nucleotide variants or deletions involving JARID2.

RESULTS

We report 16 individuals in 15 families with a deletion or single-nucleotide variant in JARID2. Several of these variants are likely to result in haploinsufficiency due to nonsense-mediated messenger RNA (mRNA) decay. All individuals have developmental delay and/or ID and share some overlapping clinical characteristics such as facial features with those who have larger deletions involving JARID2.

CONCLUSION

We report that JARID2 haploinsufficiency leads to a clinically distinct neurodevelopmental syndrome, thus establishing gene-disease validity for the purpose of diagnostic reporting.

A study of single nucleotide polymorphisms in CD157, AIM2 and JARID2 genes in Han Chinese children with autism spectrum disorder

PURPOSE

Autism spectrum disorder (ASD) is a group of developmental brain disorders caused by genetic and environmental factors. The objective of this study was to investigate whether single nucleotide polymorphisms (SNPs) in genes related to immune function were associated with ASD in Chinese Han children.

MATERIALS AND METHODS

A total of 201 children with ASD and 200 age- and gender-matched healthy controls were recruited from September 2012 to June 2106. A TaqMan probe-based approach was used to genotype SNPs corresponding to rs28532698 and rs4301112 in CD157, rs855867 in AIM2, and rs2237126 in JARID2. Case-control and case-only studies were performed to determine the contribution of SNPs to the predisposition of disease and its severity, respectively.

RESULTS

Our results revealed that the genotypes and allele frequencies of these SNPs were not significantly associated with childhood ASD and its severity in this population.

CONCLUSIONS

Results of our study suggest that these SNPs are not predictors of childhood ASD in the Chinese Han population. The discrepant results suggest the predictor roles of SNPs have to be determined in different ethnic populations due to genetic heterogeneity of ASD.

Brazilian multicenter study of association between polymorphisms in CRISPLD2 and JARID2 and non-syndromic oral clefts

BACKGROUND

Variants in the cysteine-rich secretory protein LCCL domain containing 2 gene (CRISPLD2) and in the jumonji, AT-rich interaction domain 2 gene (JARID2) were previously shown to influence non-syndromic oral cleft susceptibility. Herein, we performed a case-control study to examine the potential association of single-nucleotide polymorphisms (SNPs) in CRISPLD2 and JARID2 with non-syndromic cleft lip and/or palate (NSCL/P) in the Brazilian population. Given the ethnicity-dependent genetic predisposition to NSCL/P, we performed a structured analysis taking into account the genomic ancestry variation of each individual.

METHODS

Four SNPs in CRISPLD2 (rs1546124, rs8061351, rs2326398, and rs4783099) and four in JARID2 (rs915344, rs2299043, rs2237138, and rs2076056), that were previously reported to be associated with NSCL/P, were genotyped in 785 Brazilian patients with NSCL/P (549 with cleft lip with or without cleft palate-NSCL ± P, and 236 with cleft palate only-NSCPO) and 693 unaffected Brazilian controls. Genomic ancestry was assessed with a set of 40 biallelic short insertion/deletion variants previously validated as ancestry informative markers of the Brazilian population.

RESULTS

After adjustment of ancestry variations, allelic analysis revealed marginal associations between the CRISPLD2 rs4783099 T allele and increased risk for NSCPO (OR: 1.31, 95% CI: 1.05-1.62, P = 0.01) and between JARID2 rs2237138 and decreased NSCL ± P risk (OR: 0.80, 95% CI: 0.67-0.97, P = 0.02). Haplotype analysis indicated a lack of association between JARID2 haplotypes and non-syndromic oral cleft risk.

CONCLUSIONS

Our results suggest that CRISPLD2 rs4783099 may represent a risk factor for NSCPO while JARID2 rs2237138 shows a protective effect against NSCL ± P in the Brazilian population.

JARID2 inhibits leukemia cell proliferation by regulating CCND1 expression

It has recently been shown that JARID2 contributes to the malignant character of solid tumors, such as epithelial-mesenchymal transition in lung and colon cancer cell lines, but its role in leukemia progression is unexplored. In this study, we explored the effect and underlying molecular mechanism of JARID2 on leukemia cell proliferation. Real-time PCR and Western assay were carried out to detect JARID2 and CCND1 expression. Cell number and cell cycle change were detected using hemocytometer and flow cytometry, and a ChIP assay was utilized to investigate JARID2 and H3K27me3 enrichment on the CCND1 promoter. JARID2 is down-regulated in B-chronic lymphocytic leukemia (B-CLL) and acute monocytic leukemia (AMOL), and knockdown of JARID2 promotes leukemia cell proliferation via acceleration of the G1/S transition. Conversely, ectopic expression of JARID2 inhibits these malignant phenotypes. Mechanistic studies show that JARID2 negatively regulates CCND1 expression by increasing H3K27 trimethylation on the CCND1 promoter. Our findings indicate that JARID2 is a negative regulator of leukemia cell proliferation, and functions as potential tumor suppressor in leukemia.

Role of PRC2-associated factors in stem cells and disease

The Polycomb group (PcG) of proteins form chromatin-binding complexes with histone-modifying activity. The two main PcG repressive complexes studied (PRC1 and PRC2) are generally associated with chromatin in its repressed state. PRC2 is responsible for methylation of histone H3 at lysine 27 (H3K27me3), an epigenetic mark that is linked with numerous biological processes, including development, adult homeostasis and cancer. The core canonical complex PRC2, which contains the EZH1/2, SUZ12 and EED proteins, may be extended and functionally manipulated through interactions with several other proteins. In this review, we focus on these PRC2-associated proteins. As PRC2 functions are diverse, the variability conferred by these sub-stoichiometrically associated members may help to understand specific changes in PRC2 activity, chromatin recruitment and distribution required for gene repression.

Embryonic stem cell-specific signature in cervical cancer

The wide range of invasive and noninvasive lesion phenotypes associated with high-risk human papillomavirus (HR-HPV) infection in cervical cancer (CC) indicates that not only the virus but also specific cervical epithelial cells in the transformation zone (TZ), such as stem cells (SCs), play an important part in the development of cervical neoplasia. In this review, we focused in an expression signature that is specific to embryonic SCs and to poorly differentiated cervical malignant tumors and we hypothesize that this expression signature may play an important role to promote cell growth, survival, colony formation, lack of adhesion, as well as cell invasion and migration in CC.

6p22.3 deletion: report of a patient with autism, severe intellectual disability and electroencephalographic anomalies

Background

The interstitial 6p deletions, involving the 6p22-p24 chromosomal region, are rare events characterized by variable phenotypes and no clear genotype-phenotype correlation has been established so far.

Results

High resolution array-CGH identified 1 Mb de novo interstitial deletion in 6p22.3 chromosomal region in a patient affected by severe Intellectual Disability (ID), Autism Spectrum Disorders (ASDs), and electroencephalographic anomalies. This deletion includes ATXN1, DTNBP1, JARID2 and MYLIP genes, known to play an important role in the brain, and the GMPR gene whose function in the nervous system is unknown.

Conclusions

We support the suggestion that ATXN1, DTNBP1, JARID2 and MYLIP are candidate genes for the pathophysiology of ASDs and ID, and we propose that deletion of DTNBP1 and/or JARID2 contributes to the hypotonia phenotype.

Deletions in chromosome 6p22.3-p24.3, including ATXN1, are associated with developmental delay and autism spectrum disorders

Interstitial deletions of the short arm of chromosome 6 are rare and have been associated with developmental delay, hypotonia, congenital anomalies, and dysmorphic features. We used array comparative genomic hybridization in a South Carolina Autism Project (SCAP) cohort of 97 subjects with autism spectrum disorders (ASDs) and identified an ~ 5.4 Mb deletion on chromosome 6p22.3-p23 in a 15-year-old patient with intellectual disability and ASDs. Subsequent database queries revealed five additional individuals with overlapping submicroscopic deletions and presenting with developmental and speech delay, seizures, behavioral abnormalities, heart defects, and dysmorphic features. The deletion found in the SCAP patient harbors ATXN1, DTNBP1, JARID2, and NHLRC1 that we propose may be responsible for ASDs and developmental delay.

Comprehensive gene expression analysis of human embryonic stem cells during differentiation into neural cells

Global gene expression analysis of human embryonic stem cells (hESCs) that differentiate into neural cells would help to further define the molecular mechanisms involved in neurogenesis in humans. We performed a comprehensive transcripteome analysis of hESC differentiation at three different stages: early neural differentiation, neural ectoderm, and differentiated neurons. We identified and validated time-dependent gene expression patterns and showed that the gene expression patterns reflect early ESC differentiation. Sets of genes are induced in primary ectodermal lineages and then in differentiated neurons, constituting consecutive waves of known and novel genes. Pathway analysis revealed dynamic expression patterns of members of several signaling pathways, including NOTCH, mTOR and Toll like receptors (TLR), during neural differentiation. An interaction network analysis revealed that the TGFβ family of genes, including LEFTY1, ID1 and ID2, are possible key players in the proliferation and maintenance of neural ectoderm. Collectively, these results enhance our understanding of the molecular dynamics underlying neural commitment and differentiation.

Inactive yet indispensable: the tale of Jarid2

Methylation of histone tails is believed to be important for the establishment and inheritance of gene expression programs during development. Jarid2/Jumonji is the founding member of a family of chromatin modifiers with histone demethylase activity. Although Jarid2 contains amino acid substitutions that are thought to abolish its catalytic activity, it is essential for the development of multiple organs in mice. Recent studies have shown that Jarid2 is a component of the polycomb repressive complex 2 and is required for embryonic stem (ES) cell differentiation. Here, we discuss current literature on the function of Jarid2 and hypothesize that defects resulting from Jarid2 deficiency arise from a failure to correctly prime genes in ES cells that are required for later stages in development.

Chromosomal abnormalities associated with neural tube defects (II): partial aneuploidy

Fetuses with neural tube defects (NTDs) carry a risk of chromosomal abnormalities. The risk varies with maternal age, gestational age at diagnosis, association with other structural abnormalities, and family history of chromosome aberrations. This article provides a comprehensive review of structural chromosomal abnormalities associated with NTDs, such as del(13q), r(13), dup(2p), del(2q), del(1p), del(1q), dup(1q), del(3p), dup(3p), del(3q), dup(3q), del(4p), dup(4p), del(4q), dup(4q), del(5p), del(6p), dup(6q), del(6q), dup(7p), del(7q), dup(8q), del(9p), del(10q), del(11q), dup(11q), dup(12p), dup(14q), del(14q), del(15q), dup(16q), del(18q), r(18), dup(20p), +i(20p), del(22q), del(Xp), and dup(Xq). NTDs may be associated with aneuploidy. Perinatal identification of NTDs should alert one to the possibility of chromosomal abnormalities and prompt a thorough cytogenetic investigation and genetic counseling.

Roles of jumonji and jumonji family genes in chromatin regulation and development

The jumonji (jmj) gene was identified by a mouse gene trap approach and has essential roles in the development of multiple tissues. The Jmj protein has a DNA binding domain, ARID, and two conserved jmj domains (jmjN and jmjC). In many diverse species including bacteria, fungi, plants, and animals, there are many jumonji family proteins that have only the jmjC domain or both jmj domains. Recently, Jmj protein was found to be a transcriptional repressor. Several proteins in the jumonji family are involved in transcriptional repression and/or chromatin regulation. Most recently, one of the human members has been shown to be a histone demethylase, and the jmjC domain is essential for the demethylase activity. Meanwhile, more and more evidence indicating that the jumonji family proteins play important roles during development is accumulating. Many proteins in the jumonji family may regulate chromatin and gene expression, and control development through various signaling pathways. Here, we highlight the roles of jmj and jumonji family proteins in chromatin regulation and development.

Roles of JUMONJI in mouse embryonic development

Cardiac development is a complex biological process requiring the integration of cell specification, differentiation, migration, proliferation, and morphogenesis. Although significant progress has been made recently in understanding the molecular basis of cardiac development, mechanisms of transcriptional control of cardiac development remain largely unknown. In search for the developmentally important genes, the jumonji gene (jmj) was identified by gene trap technology and characterized as a critical nuclear factor for mouse embryonic development. Jmj has been shown to play important roles in cardiovascular development, neural tube fusion process, hematopoiesis, and liver development in mouse embryos. The amino acid sequence of the JUMONJI protein (JMJ) reveals that JMJ belongs to the AT-rich interaction domain transcription factor family and more recently has been described as a member of the JMJ transcription factor family. Here, we review the roles of jmj in multiple organ development with a focus on cardiovascular development in mice.

The structure of the Dead ringer-DNA complex reveals how AT-rich interaction domains (ARIDs) recognize DNA

The AT-rich interaction domain (ARID) is a DNA-binding module found in many eukaryotic transcription factors. Using NMR spectroscopy, we have determined the first ever three-dimensional structure of an ARID--DNA complex (mol. wt 25.7 kDa) formed by Dead ringer from Drosophila melanogaster. ARIDs recognize DNA through a novel mechanism involving major groove immobilization of a large loop that connects the helices of a non-canonical helix-turn-helix motif, and through a concomitant structural rearrangement that produces stabilizing contacts from a beta-hairpin. Dead ringer's preference for AT-rich DNA originates from three positions within the ARID fold that form energetically significant contacts to an adenine-thymine base step. Amino acids that dictate binding specificity are not highly conserved, suggesting that ARIDs will bind to a range of nucleotide sequences. Extended ARIDs, found in several sequence-specific transcription factors, are distinguished by the presence of a C-terminal helix that may increase their intrinsic affinity for DNA. The prevalence of serine amino acids at all specificity determining positions suggests that ARIDs within SWI/SNF-related complexes will interact with DNA non-sequence specifically.

Definitive But Not Primitive Hematopoiesis Is Impaired injumonji Mutant Mice

A novel gene, jumonji was identified by a mouse gene trap strategy. The jumonji gene encodes a protein containing a putative DNA binding domain. The mice homozygous for jumonjigene with a BALB/cA genetic background show hypoplasia of the fetal liver and embryonic lethality, suggesting impaired hematopoiesis. In the peripheral blood of jumonji mutant embryos, the number of fetal liver–derived definitive erythrocytes, but not yolk sac–derived primitive erythrocytes, showed a marked reduction, suggesting thatjumonji mutants die of anemia. The defects of definitive erythrocytes in jumonji mutants seemed to be caused by a decrease in the numbers of multiple hematopoietic progenitors including colony-forming unit-spleen (CFU-S) in the fetal liver. However, hematopoietic stem cells (HSCs) in the fetal liver of jumonjimutants could reconstitute the hematopoietic system of lethally irradiated recipients. In the fetal liver, the jumonji gene is expressed in fibroblastic cells and endothelial cells, but not in Lin−/c-Kit+/Sca-1+ cells known to include HSCs. These results suggest that an environmental defect induce the impaired hematopoiesis in the fetal liver ofjumonji mutant embryos.

Definitive But Not Primitive Hematopoiesis Is Impaired injumonji Mutant Mice

A novel gene, jumonji was identified by a mouse gene trap strategy. The jumonji gene encodes a protein containing a putative DNA binding domain. The mice homozygous for jumonjigene with a BALB/cA genetic background show hypoplasia of the fetal liver and embryonic lethality, suggesting impaired hematopoiesis. In the peripheral blood of jumonji mutant embryos, the number of fetal liver–derived definitive erythrocytes, but not yolk sac–derived primitive erythrocytes, showed a marked reduction, suggesting thatjumonji mutants die of anemia. The defects of definitive erythrocytes in jumonji mutants seemed to be caused by a decrease in the numbers of multiple hematopoietic progenitors including colony-forming unit-spleen (CFU-S) in the fetal liver. However, hematopoietic stem cells (HSCs) in the fetal liver of jumonjimutants could reconstitute the hematopoietic system of lethally irradiated recipients. In the fetal liver, the jumonji gene is expressed in fibroblastic cells and endothelial cells, but not in Lin−/c-Kit+/Sca-1+ cells known to include HSCs. These results suggest that an environmental defect induce the impaired hematopoiesis in the fetal liver ofjumonji mutant embryos.

A novel DNA-binding motif shares structural homology to DNA replication and repair nucleases and polymerases

A novel class of DNA-binding domains has been established from at least sixteen recently identified DNA-binding proteins. The three-dimensional structure of one of these domains, Mrf-2, has been solved using NMR methods. This structure is significantly different from known DNA-binding domain structures. The mechanism of DNA recognition by this motif has been suggested based on conserved residues, surface electrostatic potentials and chemical shift changes. This new DNA-binding motif shares structural homology with T4 RNase H, E. coli endonuclease III and Bacillus subtilis DNA polymerase I. The structural homology suggests a mechanism for substrate recognition by these enzymes.

The human necdin gene, NDN, is maternally imprinted and located in the Prader-Willi syndrome chromosomal region

Prader-Willi syndrome (PWS) is a neurogenetic disorder that results from the absence of a normal paternal contribution to the 15q11-13 region. The clinical manifestations of PWS are a transient severe hypotonia in the newborn period, with mental retardation, hypogonadism and obesity observed later in development. Five transcripts with exclusive expression from the paternal allele have been isolated, but none of these has been shown to be involved in PWS. In this study, we report the isolation and characterization of NDN, a new human imprinted gene. NDN is exclusively expressed from the paternal allele in the tissues analysed and is located in the PWS region. It encodes a putative protein homologous to the mouse brain-specific NECDIN protein, NDN; as in mouse, expression in brain is restricted to post-mitotic neurons. NDN displays several characteristics of an imprinted locus, including allelic DNA methylation and asynchronous DNA replication. A complete lack of NDN expression in PWS brain and fibroblasts indicates that the gene is expressed exclusively from the paternal allele in these tissues and suggests a possible role of this new gene in PWS.