Joint match probabilities for Y chromosomal and autosomal markers

Empirical tests of association between Y chromosome and autosomal markers are presented and a theoretical framework for determining a joint match probability is recommended. Statistical analyses of association were performed in 16 US populations between the autosomal genotypes from loci CSF1PO, FGA, THO1, TPOX, vWA, D3S1358, D5S818, D7S820, D8S1179, D13S317, D16S539, D18S512, D21S11 and Y chromosome haplotypes from loci DYS19, DYS385ab, DYS389I, DYS389II, DYS390, DYS391, DYS392, DYS393, DYS438, and DYS439. The sample populations include individuals of European-, African-, Hispanic-, Native-, and Asian-American ancestry. The results are consistent with independence of Y and autosomal markers, although small amounts of dependence would likely have escaped our tests. Given the data in hand, we suggest it is appropriate to compute joint match probabilities by multiplying the Y haplotype frequency with the appropriately corrected autosomal frequency. In addition to correcting for autosomal frequency differences between groups, a further correction may be required. Since two individuals sharing the same Y haplotype are likely to be more recently related than two randomly chosen individuals, the autosomal frequencies have to be adjusted to account for this, akin to the theta correction used to account for population substructure. The structure imposed on the autosomal frequencies conditioned in a Y match is a function of the number of markers scored and their mutation rate. However, in most settings theta<0.01. When population structure is already present in the autosomes, the additional effect due to conditioning on the Y is small. For example, if the amount of structure in the population is theta=0.01 or 0.03 (the NRCII range), then the effect of conditioning on the Y results in only a trivial increase in theta to 0.02-0.04, respectively.     

Why Medical Child Support is Important—and Complex

Courts resolving child support cases involving separated, divorced, and non‐marital children are charged with defining responsibility for health care coverage for the children under that order. This article explores historical and current medical child support requirements under Title IV‐D of the Social Security Act—the national child support enforcement (“IV‐D”) program. It analyzes legal requirements and policy recommendations, and provides a practical tool judges may use to determine whether health care coverage available to either or both parents is appropriate—that is, comprehensive, accessible, and affordable.     

Perceptions of repressed memories: A reappraisal

College students read a trial summary of a sexual abuse case. The victim in the case either claimed that (a) her memory for the abuse had been repressed for 20 years and only recently recovered during therapy, or (b) she consciously remembered the abuse for 20 years but never discussed it until recently in therapy. Participants were significantly more likely to convict the defendant when the testimony was described as nonrepressed (67%) versus repressed (58%). This effect was not modified by the age of the victim at the time the alleged abuse occurred (either 3, 8, or 13 years of age), although the younger and older victims were significantly less believable than the 8-year-old victim. Compared to female participants, male participants were significantly less likely to convict the defendant and rated the victim as significantly less believable. These findings are discussed in the context of recent research on juror reactions to repressed memory testimony.     

A comparison between direct and indirect methods available for human bite mark analysis

Comparison techniques used in bite mark analysis are many and varied, the choice of technique depending largely on personal preference. Until recently, no one technique has been shown to be better than the others, and very little research has been carried out to compare different methods. This study evaluates and compares the accuracy of direct comparisons between suspects' models and bite marks with indirect comparisons in the form of conventional traced overlays of suspects' models or a new method using photocopier-generated overlays. Artificial bite marks in pigskin were made using standardized sets of models and recorded as photographs and fingerprint powder lifts on tape. The bite mark photographs and fingerprint lifts were coded and randomized so that a blind comparison could be made with the models, traced overlays, and photocopier-generated overlays using a modified version of the American Board of Forensic Odontology Scoring (ABFO) System for Bite Marks. It was found that the photocopier-generated overlays were significantly more accurate at matching the correct bite mark to the correct models irrespective of whether the bite mark was recorded photographically or as a fingerprint lift. The photocopier-generated overlays were also found to be more sensitive at matching the correct bite marks to the correct models than the other two methods used. The modified ABFO scoring system was able to discriminate between a correct match and several incorrect matches by awarding a high score to the correct match.     

Interpretation of a 3,4-methylenedioxymethamphetamine (MDMA) blood level: discussion by means of a distribution study in two fatalities

The amphetamine derivative 3,4-methylenedioxymethamphetamine (MDMA, "Ecstasy" is a currently used or abused designer drug and fatalities are frequently encountered in forensic practice. However, the question remains open whether an MDMA blood level can be toxic or even potentially lethal. In order to provide insight in the interpretation of a detected MDMA concentration, the distribution of MDMA and its metabolite 3,4-methylenedioxyamphetamine (MDA) in various body fluids and tissues was studied and discussed in two different fatalities. Apart from peripheral blood samples (such as femoral and subclavian blood), various blood samples obtained centrally in the human body and several body fluids (such as vitreous humour) were examined. In addition, various tissues such as cardiac muscle, lungs, liver, kidneys, and brain lobes were analysed. In contrast to the peripheral blood levels, high MDMA and MDA levels were found in cardiac blood and the majority of the organs, except for the abdominal adipose tissue. The high concentrations observed in all lung lobes, the liver and stomach contents indicate that post-mortem redistribution of MDMA and MDA into cardiac blood can occur and, as a result, blood sampled centrally in the body should be avoided. Therefore, our data confirm that peripheral blood sampling remains "the golden standard". In addition, a distinct difference in peripheral blood MDMA concentrations in our two overdose cases was established (namely 0.271 and 13.508 microg/ml, respectively). Furthermore, our results suggest that, if a peripheral blood sample is not available and when putrefaction is not too pronounced, vitreous humour and iliopsoas muscle can be valuable specimens for toxicological analysis. Finally, referring to the various mechanisms of death following amphetamine intake, which can result in different survival times (e.g. cardiopulmonary complications versus hyperthermia), the anatomo-pathological findings and the toxicological results should be considered as a whole in arriving at a conclusion.     

An unusual fatality in a child due to oxycodone

An unusual fatality secondary to oxycodone in a child is reported. A 2-year-old female child was conveyed to a local hospital after exhibiting signs of rubbing of the mouth and staggering. A hospital toxicological immunoassay screen for drugs of abuse and tricyclic antidepressants was performed on a urine sample and reported as negative. She was discharged and found unresponsive the next morning. She was conveyed to a second hospital in full cardiopulmonary arrest and despite resuscitative efforts, was pronounced dead upon arrival. An autopsy was performed and postmortem specimens were submitted and screened for drugs using mainly chromatographic techniques. Quantitation was achieved by gas chromatography with nitrogen phosphorus detection. Confirmation was performed by gas chromatography/mass spectrometry. Oxycodone was the only drug detected in the following concentrations: heart blood, 1.36 mg/L; gastric contents, 7.33 mg in 33 mL (222.34 mg/L); liver, 0.2 mg/kg; and urine, 47.23 mg/L (47,230 ng/mL). In addition, immunoassay testing of the urine was positive for the opiate class of drugs. This case report demonstrates an unusual cause of death in a young child with emphasis on potential limitation in hospital urine screening tests and the importance of complete forensic toxicological testing in all child deaths.     

Y-chromosomal STR haplotypes in a population sample from continental Greece, and the islands of Crete and Chios

Eight Y chromosome short tandem repeat (STR) polymorphisms (DYS19, DYS385, DYS389I, DYS389II, DYS390, DYS391, DYS392, and DYS393) were analyzed in the sample of 117 unrelated Albanian males living in Kosovo. A general STR allelic frequency pattern in the Albanian population from Kosovo corresponds to other European populations. Fourty six haplotypes were observed in single copy. The most frequent haplotypes were (DYS19-DYS385-DYS389I-DYS389II-DYS390-DYS391-DYS392-DYS393) 14-11/11-13-29-24-11-13-13 (10.26%), 14-14/17-12-28-24-10-11-12 (9.40%), 13-16/18-13-30-24-10-11-13 (9.40%), and 14-17/17-13-31-24-10-11-13 (9.40%).     

Oxycodone intoxication in an infant: accidental or intentional exposure?

A case is presented of a 10 month old male who went into cardiac arrest at a local store. The infant subsequently expired and was autopsied at the Office of the Chief Medical Examiner, State of Maryland. The only remarkable finding was the detection of oxycodone in the postmortem specimens; the blood and liver oxycodone concentrations were 0.6 mg/L and 1.6 mg/kg, respectively. Oxycodone was identified and quantitated by gas chromatography-nitrogen-phosphorus detection and confirmed by full scan electron ionization gas chromatography-mass spectrometry. The medical examiner ruled that the cause of death was oxycodone intoxication, and the manner of death was homicide. The key toxicologic question in this case was whether or not it was reasonable for the infant to be exposed to oxycodone exclusively through breast milk or through an alternate source. It was concluded that, at best, there were serious concerns about the likelihood of drug exposure through consumption of breast milk.     

Detection of intimate partner violence in a general medicine practice

In this study, an assessment phase is undertaken to determine intimate partner violence (IPV) prevalence. An anonymous survey is followed by a chart review documenting identification of IPV. Two methods are attempted to increase assessment/documentation of IPV: a physician educational intervention and a nursing routine inquiry intervention in one quadrant of the practice. The IPV physician educational intervention includes didactic sessions, an IPV counselor, and resource information. The routine inquiry intervention involves nurses screening female patients for IPV at check-in. IPV is found to be prevalent in a general medicine clinic. An enhanced educational intervention does not increase IPV documentation. A routine inquiry intervention significantly increases documentation of lifetime IPV but does not impact current IPV identification.