Subject(s)
Bone Diseases, Metabolic/pathology , Ossification, Heterotopic/pathology , Pseudopseudohypoparathyroidism/pathology , Skin Diseases, Genetic/pathology , Skin/pathology , Bone Diseases, Metabolic/genetics , Chromogranins/genetics , GTP-Binding Protein alpha Subunits, Gs/genetics , Humans , Infant , Male , Mutation , Ossification, Heterotopic/genetics , Pseudopseudohypoparathyroidism/genetics , Skin Diseases, Genetic/geneticsABSTRACT
PURPOSE: The clinical and psychosocial outcomes associated with receiving a genetic diagnosis for developmental disorders are wide-ranging but under-studied. We sought to investigate outcomes from a subset of families who received a diagnosis through the Deciphering Developmental Disorders (DDD) study. METHODS: Individuals recruited through the Peninsula Clinical Genetics Service who received a confirmed genetic diagnosis through the DDD study before August 2019 (n = 112) were included in a clinical audit. Families with no identified clinical outcomes (n = 16) were invited to participate in semistructured telephone interviews. RESULTS: Disease-specific treatment was identified for 7 probands (6%), while 48 probands (43%) were referred for further investigations or screening and 60 probands (54%) were recruited to further research. Just 5 families (4%) opted for prenatal testing in a subsequent pregnancy, reflecting the relatively advanced maternal age in our cohort, and 42 families (38%) were given disease-specific information or signposting to patient-specific resources such as support groups. Six interviews were performed (response rate = 47%) and thematic analysis identified four major themes: reaching a diagnosis, emotional impact, family implications, and practical issues. CONCLUSION: Our data demonstrate that receiving a genetic diagnosis has substantial positive medical and psychosocial outcomes for the majority of patients and their families.
Subject(s)
Developmental Disabilities , Genetic Testing , Child , Developmental Disabilities/diagnosis , Developmental Disabilities/epidemiology , Developmental Disabilities/genetics , Emotions , Female , Humans , Pregnancy , Referral and ConsultationABSTRACT
Primary pneumococcal peritonitis is a rare infection that has been described in women but has not been previously linked with immunodeficiency. The complement system plays a central role in immune defence against Streptococcus pneumoniae and, in order to evade complement attack, pneumococci have evolved a large number of mechanisms that limit complement-mediated opsonization and subsequent phagocytosis. We investigated an apparently immunocompetent woman with primary pneumococcal peritonitis and identified a family with deficiency for complement factor I. Primary pneumococcal peritonitis should be considered a possible primary immunodeficiency presentation.
Subject(s)
Complement C3/deficiency , Hereditary Complement Deficiency Diseases/immunology , Peritonitis/immunology , Pneumococcal Infections/immunology , Streptococcus pneumoniae/immunology , Adolescent , Complement C3/immunology , Female , Hereditary Complement Deficiency Diseases/pathology , Humans , Peritonitis/pathology , Pneumococcal Infections/pathologyABSTRACT
Mosaic genetic variants can have major clinical impact. We systematically analyse trio exome sequence data from 4,293 probands from the DDD Study with severe developmental disorders for pathogenic postzygotic mosaicism (PZM) in the child or a clinically-unaffected parent, and use ultrahigh-depth sequencing to validate candidate mosaic variants. We observe that levels of mosaicism for small genetic variants are usually equivalent in both saliva and blood and ~3% of causative de novo mutations exhibit PZM; this is an important observation, as the sibling recurrence risk is extremely low. We identify parental PZM in 21 trios (0.5% of trios), resulting in a substantially increased sibling recurrence risk in future pregnancies. Together, these forms of mosaicism account for 40 (1%) diagnoses in our cohort. Likely child-PZM mutations occur equally on both parental haplotypes, and the penetrance of detectable mosaic pathogenic variants overall is likely to be less than half that of constitutive variants.
Subject(s)
Developmental Disabilities/genetics , Exome Sequencing/methods , Exome/genetics , Mosaicism , Child , Cohort Studies , Developmental Disabilities/diagnosis , Female , Genetic Testing/methods , Genetic Variation , Haplotypes/genetics , High-Throughput Nucleotide Sequencing , Humans , Male , Maternal Inheritance/genetics , Parents , Paternal Inheritance/geneticsABSTRACT
BACKGROUND: Bainbridge-Ropers syndrome (BRPS) is a recently described developmental disorder caused by de novo truncating mutations in the additional sex combs like 3 (ASXL3) gene. To date, there have been fewer than 10 reported patients. OBJECTIVES: Here, we delineate the BRPS phenotype further by describing a series of 12 previously unreported patients identified by the Deciphering Developmental Disorders study. METHODS: Trio-based exome sequencing was performed on all 12 patients included in this study, which found a de novo truncating mutation in ASXL3. Detailed phenotypic information and patient images were collected and summarised as part of this study. RESULTS: By obtaining genotype:phenotype data, we have been able to demonstrate a second mutation cluster region within ASXL3. This report expands the phenotype of older patients with BRPS; common emerging features include severe intellectual disability (11/12), poor/ absent speech (12/12), autistic traits (9/12), distinct face (arched eyebrows, prominent forehead, high-arched palate, hypertelorism and downslanting palpebral fissures), (9/12), hypotonia (11/12) and significant feeding difficulties (9/12) when young. DISCUSSION: Similarities in the patients reported previously in comparison with this cohort included their distinctive craniofacial features, feeding problems, absent/limited speech and intellectual disability. Shared behavioural phenotypes include autistic traits, hand-flapping, rocking, aggressive behaviour and sleep disturbance. CONCLUSIONS: This series expands the phenotypic spectrum of this severe disorder and highlights its surprisingly high frequency. With the advent of advanced genomic screening, we are likely to identify more variants in this gene presenting with a variable phenotype, which this study will explore.
Subject(s)
Developmental Disabilities/genetics , Developmental Disabilities/pathology , Loss of Function Mutation/genetics , Phenotype , Transcription Factors/genetics , Adult , Child , Child, Preschool , Developmental Disabilities/physiopathology , Female , Humans , Male , Exome Sequencing , Young AdultABSTRACT
Baraitser-Winter cerebrofrontofacial syndrome (BWCFF) (BRWS; MIM #243310, 614583) is a rare developmental disorder affecting multiple organ systems. It is characterised by intellectual disability (mild to severe) and distinctive facial appearance (metopic ridging/trigonocephaly, bilateral ptosis, hypertelorism). The additional presence of cortical malformations (pachygyria/lissencephaly) and ocular colobomata are also suggestive of this syndrome. Other features include moderate short stature, contractures, congenital cardiac disease and genitourinary malformations. BWCFF is caused by missense mutations in the cytoplasmic beta- and gamma-actin genes ACTB and ACTG1. We provide an overview of the clinical characteristics (including some novel findings in four recently diagnosed patients), diagnosis, management, mutation spectrum and genetic counselling.
Subject(s)
Abnormalities, Multiple/genetics , Actins/genetics , Craniofacial Abnormalities/genetics , Developmental Disabilities/genetics , Growth Disorders/genetics , Hydrocephalus/genetics , Mental Retardation, X-Linked/genetics , Obesity/genetics , Abnormalities, Multiple/diagnosis , Abnormalities, Multiple/physiopathology , Craniofacial Abnormalities/diagnosis , Craniofacial Abnormalities/physiopathology , Developmental Disabilities/diagnosis , Developmental Disabilities/physiopathology , Facies , Genetic Counseling , Growth Disorders/diagnosis , Growth Disorders/physiopathology , Humans , Hydrocephalus/diagnosis , Hydrocephalus/physiopathology , Mental Retardation, X-Linked/diagnosis , Mental Retardation, X-Linked/physiopathology , Mutation, Missense/genetics , Obesity/diagnosis , Obesity/physiopathologyABSTRACT
BACKGROUND: A combined measure of two common psychosocial stressors, called job pressure has previously been shown to be strongly associated with poor mental health in high status workers. This study tests the generalizability of this association to lower status workers. METHODS: A national random sample of cleaners and clerical workers was obtained from the New Zealand (NZ) electoral roll by occupational title (n = 596). Cross-sectional data on job stressors, demographics, and mental health (GHQ-12) was collected by computer-assisted telephone interviews. RESULTS: Combined exposure to low job control, high job demands, and job insecurity (high job pressure) was associated with markedly elevated odds (13-fold or higher) of poor mental health after adjustment for age, sex, occupation, and education. CONCLUSION: Combined with previous findings this suggests simultaneous exposure to more than one occupational psychosocial stressor may greatly increase the risk of poor mental health among both lower and higher status workers. This report adds to the larger literature in this area, supporting the need for expanded policy and practice intervention to reduce job stressors across the working population.
Subject(s)
Mental Disorders/epidemiology , Mental Health , Occupational Diseases/epidemiology , Occupational Exposure/adverse effects , Stress, Psychological/complications , Cross-Sectional Studies , Female , Health Status , Humans , Interview, Psychological , Logistic Models , Male , Mental Disorders/etiology , Mental Disorders/psychology , New Zealand/epidemiology , Occupational Diseases/etiology , Occupational Diseases/psychology , Psychometrics , Self Report , Surveys and Questionnaires , Workplace/psychologyABSTRACT
BACKGROUND: self-reported occupational histories are an important means for collecting historical data in epidemiological studies. An occupational history calendar (OHC) has been developed for use alongside a national occupational hazard surveillance tool. This study presents the systematic development of the OHC and compares work histories collected via this calendar to those collected via a traditional questionnaire. METHODS: the paper describes the systematic development of an OHC for use in the general working population. A comparison of data quality and recall was undertaken in 51 participants where both tools were administered. RESULTS: the OHC enhanced job recall compared with the traditional questionnaire. Good agreement in the data captured by both tools was observed, with the exception of hazard exposures. CONCLUSIONS: a calendar approach is suitable for collecting occupational histories from the general working population. Despite enhancing job recall the OHC approach has some shortcomings outweighing this advantage in large-scale population surveillance.
Subject(s)
Occupational Exposure/statistics & numerical data , Occupational Health/statistics & numerical data , Adolescent , Adult , Aged , Female , Focus Groups , Humans , Male , Mental Recall , Middle Aged , New Zealand , Pilot Projects , Population Surveillance/methods , Qualitative Research , Research Design , Risk Factors , Surveys and Questionnaires , Young AdultABSTRACT
BACKGROUND: Deletions of chromosome 19 have rarely been reported, with the exception of some patients with deletion 19q13.2 and Blackfan-Diamond syndrome due to haploinsufficiency of the RPS19 gene. Such a paucity of patients might be due to the difficulty in detecting a small rearrangement on this chromosome that lacks a distinct banding pattern. Array comparative genomic hybridisation (CGH) has become a powerful tool for the detection of microdeletions and microduplications at high resolution in patients with syndromic mental retardation. METHODS AND RESULTS: Using array CGH, this study identified three interstitial overlapping 19q13.11 deletions, defining a minimal critical region of 2.87 Mb, associated with a clinically recognisable syndrome. The three patients share several major features including: pre- and postnatal growth retardation with slender habitus, severe postnatal feeding difficulties, microcephaly, hypospadias, signs of ectodermal dysplasia, and cutis aplasia over the posterior occiput. Interestingly, these clinical features have also been described in a previously reported patient with a 19q12q13.1 deletion. No recurrent breakpoints were identified in our patients, suggesting that no-allelic homologous recombination mechanism is not involved in these rearrangements. CONCLUSIONS: Based on these results, the authors suggest that this chromosomal abnormality may represent a novel clinically recognisable microdeletion syndrome caused by haploinsufficiency of dosage sensitive genes in the 19q13.11 region.
Subject(s)
Abnormalities, Multiple/genetics , Chromosome Disorders/genetics , Chromosomes, Human, Pair 19 , Comparative Genomic Hybridization/methods , Oligonucleotide Array Sequence Analysis/methods , Sequence Deletion , Humans , In Situ Hybridization, Fluorescence , Intellectual Disability , Karyotyping , MaleABSTRACT
BACKGROUND: The chromosome 17q21.31 microdeletion syndrome is a novel genomic disorder that has originally been identified using high resolution genome analyses in patients with unexplained mental retardation. AIM: We report the molecular and/or clinical characterisation of 22 individuals with the 17q21.31 microdeletion syndrome. RESULTS: We estimate the prevalence of the syndrome to be 1 in 16,000 and show that it is highly underdiagnosed. Extensive clinical examination reveals that developmental delay, hypotonia, facial dysmorphisms including a long face, a tubular or pear-shaped nose and a bulbous nasal tip, and a friendly/amiable behaviour are the most characteristic features. Other clinically important features include epilepsy, heart defects and kidney/urologic anomalies. Using high resolution oligonucleotide arrays we narrow the 17q21.31 critical region to a 424 kb genomic segment (chr17: 41046729-41470954, hg17) encompassing at least six genes, among which is the gene encoding microtubule associated protein tau (MAPT). Mutation screening of MAPT in 122 individuals with a phenotype suggestive of 17q21.31 deletion carriers, but who do not carry the recurrent deletion, failed to identify any disease associated variants. In five deletion carriers we identify a <500 bp rearrangement hotspot at the proximal breakpoint contained within an L2 LINE motif and show that in every case examined the parent originating the deletion carries a common 900 kb 17q21.31 inversion polymorphism, indicating that this inversion is a necessary factor for deletion to occur (p<10(-5)). CONCLUSION: Our data establish the 17q21.31 microdeletion syndrome as a clinically and molecularly well recognisable genomic disorder.
Subject(s)
Abnormalities, Multiple , Chromosome Deletion , Chromosomes, Human, Pair 17/genetics , Developmental Disabilities , Abnormalities, Multiple/epidemiology , Abnormalities, Multiple/genetics , Abnormalities, Multiple/physiopathology , Adolescent , Adult , Child , Child, Preschool , Chromosome Inversion , Developmental Disabilities/epidemiology , Developmental Disabilities/genetics , Developmental Disabilities/physiopathology , Face/pathology , Female , Humans , Infant , Male , Muscle Hypotonia/epidemiology , Muscle Hypotonia/genetics , Muscle Hypotonia/physiopathology , Oligonucleotide Array Sequence Analysis , Polymorphism, Single Nucleotide , Prevalence , Young Adult , tau ProteinsABSTRACT
MRI and neurological findings in macrocephaly-cutis marmorata telangiectatica congenita syndrome: report of ten cases and review of the literature: We describe the clinical history and magnetic resonance imaging (MRI) findings in 10 children with the Macrocephaly-Cutis Marmorata Telangiectatica Congenita syndrome (M-CMTC--MIM 602501). This syndrome has recently been delineated within the general group of patients with Cutis Marmorata Telangiectatica (CMTC) as a distinct and easily recognisable entity. In contrast to most children with CMTC, patients with M-CMTC syndrome have a high risk of neurological abnormalities, such as hydrocephalus, megalencephaly, developmental delay and mental retardation. An MRI scan showed structural cerebral abnormalities in all of our patients, including megalencephaly, asymmetry of the cerebral hemispheres and abnormally increased signal of white matter. Seven patients also had Chiari type I malformation. Reviewing all reported cases, we propose appropriate surveillance for known complications.
Subject(s)
Craniofacial Abnormalities/diagnosis , Magnetic Resonance Imaging , Skin Abnormalities/diagnosis , Skin Diseases, Vascular/diagnosis , Telangiectasis/diagnosis , Abnormalities, Multiple/diagnosis , Abnormalities, Multiple/genetics , Brain/pathology , Child , Child, Preschool , Craniofacial Abnormalities/genetics , Developmental Disabilities/diagnosis , Developmental Disabilities/genetics , Female , Follow-Up Studies , Functional Laterality/genetics , Growth Disorders/diagnosis , Growth Disorders/genetics , Humans , Infant , Infant, Newborn , Phenotype , Skin Abnormalities/genetics , Skin Diseases, Vascular/genetics , Syndactyly/diagnosis , Syndactyly/genetics , Syndrome , Telangiectasis/geneticsABSTRACT
BACKGROUND: Sotos syndrome is characterised by learning difficulties, overgrowth, and a typical facial appearance. Microdeletions at 5q35.3, encompassing NSD1, are responsible for approximately 10% of non-Japanese cases of Sotos. In contrast, a recurrent approximately 2 Mb microdeletion has been reported as responsible for approximately 50% of Japanese cases of Sotos. METHODS: We screened 471 cases for NSD1 mutations and deletions and identified 23 with 5q35 microdeletions. We investigated the deletion size, parent of origin, and mechanism of generation in these and a further 10 cases identified from published reports. We used "in silico" analyses to investigate whether repetitive elements that could generate microdeletions flank NSD1. RESULTS: Three repetitive elements flanking NSD1, designated REPcen, REPmid, and REPtel, were identified. Up to 18 cases may have the same sized deletion, but at least eight unique deletion sizes were identified, ranging from 0.4 to 5 Mb. In most instances, the microdeletion arose through interchromosomal rearrangements of the paternally inherited chromosome. CONCLUSIONS: Frequency, size, and mechanism of generation of 5q35 microdeletions differ between Japanese and non-Japanese cases of Sotos. Our microdeletions were identified from a large case series with a broad range of phenotypes, suggesting that sample selection variability is unlikely as a sole explanation for these differences and that variation in genomic architecture might be a contributory factor. Non-allelic homologous recombination between REPcen and REPtel may have generated up to 18 microdeletion cases in our series. However, at least 15 cannot be mediated by these repeats, including at least seven deletions of different sizes, implicating multiple mechanisms in the generation of 5q35 microdeletions.
Subject(s)
Chromosomes, Human, Pair 5/genetics , Gene Deletion , Growth Disorders/genetics , Learning Disabilities/genetics , Abnormalities, Multiple/genetics , Alleles , Female , Gene Frequency , Histone Methyltransferases , Histone-Lysine N-Methyltransferase , Humans , Intracellular Signaling Peptides and Proteins/genetics , Male , Microsatellite Repeats/genetics , Nuclear Proteins/genetics , Phenotype , Syndrome , Terminal Repeat SequencesABSTRACT
AIMS: To assess the significance of individual risk factors in the development of occupational asthma of aluminium smelting (OAAS). METHODS: A matched case-control study nested in a cohort of 545 workers employed in areas with moderate to high levels of smelting dust and fume. The cohort comprised those who had their first pre-employment medical examination between 1 July 1982 and 1 July 1995; follow up was until 31 December 2000. Forty five cases diagnosed with OAAS and four controls per case were matched for the same year of pre-employment and age within +/-5 years. The pre-employment medical questionnaires were examined, blinded as to case-control status, and information obtained on demographics and details of allergic symptoms, respiratory risk factors, respiratory symptoms, and spirometry. Data from the subsequent medical notes yielded subsequent history of hay fever, family history of asthma, full work history, date of termination or diagnosis, and tobacco smoking history at the end-point. RESULTS: There was a significant positive association between hay fever diagnosed either at or during employment and OAAS (adjusted OR 3.58, 95% CI 1.57 to 8.21). A higher forced expiratory ratio (FEV1/FVC%) at employment reduced the risk of developing OAAS (adjusted OR 0.93, 95% CI 0.88 to 0.99). The risk of OAAS was more than three times higher in individuals with an FER of 70.0-74.9% than in individuals with an FER > or =80.0% (adjusted OR 3.46, 95% CI 1.01 to 11.89). CONCLUSIONS: Individuals with hay fever may be more susceptible to occupational asthma when exposed to airborne irritants in aluminium smelting. The pathological basis may be reduced nasal filtration and increased bronchial hyperresponsiveness.
Subject(s)
Aluminum/toxicity , Asthma/etiology , Metallurgy , Occupational Diseases/etiology , Adult , Asthma/physiopathology , Case-Control Studies , Cohort Studies , Forced Expiratory Volume , Humans , Male , Occupational Diseases/physiopathology , Occupational Exposure/adverse effects , Rhinitis, Allergic, Seasonal/complications , Risk Factors , Time Factors , Vital CapacityABSTRACT
The underlying causes of learning disability and dysmorphic features in many patients remain unidentified despite extensive investigation. Routine karyotype analysis is not sensitive enough to detect subtle chromosome rearrangements (less than 5 Mb). The presence of subtle DNA copy number changes was investigated by array-CGH in 50 patients with learning disability and dysmorphism, employing a DNA microarray constructed from large insert clones spaced at approximately 1 Mb intervals across the genome. Twelve copy number abnormalities were identified in 12 patients (24% of the total): seven deletions (six apparently de novo and one inherited from a phenotypically normal parent) and five duplications (one de novo and four inherited from phenotypically normal parents). Altered segments ranged in size from those involving a single clone to regions as large as 14 Mb. No recurrent deletion or duplication was identified within this cohort of patients. On the basis of these results, we anticipate that array-CGH will become a routine method of genome-wide screening for imbalanced rearrangements in children with learning disability.
Subject(s)
Chromosome Aberrations , Chromosome Disorders/genetics , Cytogenetic Analysis/methods , Intellectual Disability/genetics , Learning Disabilities/genetics , Oligonucleotide Array Sequence Analysis/methods , Adolescent , Adult , Child , Child, Preschool , Chromosome Deletion , Female , Humans , MaleSubject(s)
Marfan Syndrome/genetics , Microfilament Proteins/genetics , Mutation/genetics , Adolescent , Adult , Child , Chromatography, High Pressure Liquid/methods , DNA Mutational Analysis/methods , Electrophoresis, Polyacrylamide Gel/methods , Fibrillin-1 , Fibrillins , Gene Amplification/genetics , Heteroduplex Analysis/methods , Humans , Marfan Syndrome/diagnosis , Middle Aged , Nucleic Acid Conformation , Nucleic Acid Denaturation/genetics , PhenotypeABSTRACT
AIM: To describe the health of farmers in Southland. METHODS: Coss-sectional study of a random sample of farmers in Southland. RESULTS: 586 individuals were interviewed from 286 farms with a response rate of 65.4%. The prevalence of at least one injury in the last twelve months which prevented normal farm work was 17.1%. Low back pain was common with 54.6% reporting such an episode in the last twelve months. Noise-induced hearing loss was prevalent among men with 28.7% of those 45 years and over being affected. Levels of asthma appeared low with a point prevalence of 6.8%, with 4.6% on medication. There were 19.3% of male farmers who were obese. The prevalence of alcohol use disorder among men aged 15-24 years was 57.4%, and 39.0% among farm workers. Similarly, 32.0% of men in this age-group smoked, with 35.6% of farm workers being smokers. CONCLUSIONS: Farmers experienced high levels of injury, low back pain and noise-induced hearing loss. Community intervention programmes to prevent injury remain a priority for farmers, although lifestyle factors should also be addressed, particularly among farm workers.
Subject(s)
Agriculture , Occupational Diseases/epidemiology , Adolescent , Adult , Age Distribution , Aged , Cross-Sectional Studies , Female , Health Status , Health Surveys , Humans , Male , Middle Aged , New Zealand/epidemiology , Occupational Diseases/diagnosis , Prevalence , Risk Factors , Rural Population , Sampling Studies , Sex DistributionABSTRACT
The present authors conducted a study of the occurrence of victimization and the perpetration of sexual abuse among 43 in-patients with intellectual disability aged between 9 and 21 years who were admitted to a child and adolescent psychiatric in-patient department over a period of 5 years. A retrospective case-note review was employed that explored the nature and severity of abuse in relation to the age, gender and level of disability. The prevalence of abuse or abusive behaviour, i.e. 14% of 300 admissions, did not change over time. In 13 out of the 43 cases, the issue of sexual abuse was identified after admission. Victimization alone occurred in 21 cases, perpetration alone in six cases, and both victimization and perpetration in 16 cases. Fifty per cent of the victims had been abused by a member of their close or extended family. Most cases (62%) were adolescents. There was only one instance of a victim being abused by a female. However, there were five girls who were perpetrators, all of whom had previously been victims. By contrast, 11 out of the 17 male perpetrators had been victims. Despite difficulties of disclosure, it was possible to establish that severely disabled patients had suffered sexual abuse. The present data support theories which (1) recognize gender differences in sexual abuse patterns and (2) have a developmental perspective, incorporating the influence of adolescence.
Subject(s)
Child Abuse, Sexual/statistics & numerical data , Intellectual Disability/epidemiology , Adolescent , Child , Child Abuse, Sexual/diagnosis , Child Abuse, Sexual/psychology , Crime Victims/legislation & jurisprudence , Female , Humans , Intellectual Disability/diagnosis , Intellectual Disability/psychology , Male , Patient Admission/statistics & numerical data , United KingdomABSTRACT
The present study addressed two issues using a sample of child and adolescent victims and perpetrators of sexual abuse: (1) the extent of post-traumatic stress disorder (PTSD) in the sample; and (2) the possible distinction between perpetrators whose motivations were sexually impulsive, and those who were controlling and abuse-reactive. Retrospective case material from 43 cases (21 victims only, and 22 perpetrators, of whom 16 were also victims) provided the data. Post-traumatic symptomatology was not common. Only one case of PTSD was found. Perpetrators could be distinguished by whether they had suffered sexual abuse alone, sexual and physical abuse, or neither. The proposed distinction between perpetrators received support. Sexual abuse directed at younger victims was associated with earlier experience of multiple forms of abuse. The present data does not support the view that post-traumatic symptoms following victimization are a mediator of sexual abuse perpetration. It is argued that an elaboration of the Williams & New developmental model of perpetration better fits the data.