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Rigorous evaluation and optimization pending

aIn the United Kingdom, the recommended quality for microdeletion detection is quality score 7, as laid out by the National External Quality Assessment Scheme (NEQAS) (for information, see http://www.well.ox.ac.uk/~sknight/NEQAS/NEQASBandingCriteria.htm and http://www.ukneqas.org.uk/ Directory/GENET/clincyto.htm). In practice, few laboratories achieve this standard routinely, although would endeavor to do so for selected cases, on request. According to the UK NEQAS for Clinical Cytogenetics 2000, sample slides submitted by the United Kingdom's 40 Clinical Cytogenetics laboratories ranged in quality from quality score 4 to quality score 8.

Source: Dr. Ros Hastings, organizer of UK NEQAS for Clinical Cytogenetics, personal communication.

aIn the United Kingdom, the recommended quality for microdeletion detection is quality score 7, as laid out by the National External Quality Assessment Scheme (NEQAS) (for information, see http://www.well.ox.ac.uk/~sknight/NEQAS/NEQASBandingCriteria.htm and http://www.ukneqas.org.uk/ Directory/GENET/clincyto.htm). In practice, few laboratories achieve this standard routinely, although would endeavor to do so for selected cases, on request. According to the UK NEQAS for Clinical Cytogenetics 2000, sample slides submitted by the United Kingdom's 40 Clinical Cytogenetics laboratories ranged in quality from quality score 4 to quality score 8.

Source: Dr. Ros Hastings, organizer of UK NEQAS for Clinical Cytogenetics, personal communication.

pediatrics clinics, and so who then, among these vast numbers, should be investigated for subtle subtelomeric aberrations? Detection rates are higher among those with moderate to severe mental retardation, but screening all individuals in this group is usually considered impractical because of the cost. One argument is that the high rate of familial occurrence does justify blanket screening of all individuals with unexplained MR on the grounds that in familial cases, all results are informative.[3] However, a more cost-effective strategy would be to identify clinically a subgroup in whom small deletions occur at a much higher frequency. But is this possible? One approach that has been taken has been to investigate the clinical phenotypes of all of those MR individuals diagnosed with a subtelomeric rearrangement and to identify features that occur more frequently in this group.[25] The results indicate that prenatal onset of growth retardation and a positive family history for developmental delay are good indicators for subtelomeric anomalies. These criteria, plus features suggestive of a chromosomal phe-notype, have been included in a five-item clinical checklist, predicted to improve the diagnostic pickup rate of subtelomeric rearrangements among the developmen-tally delayed.[25] However, this checklist is not routinely adopted in clinical practice, presumably because diagnoses might be missed.

A more clinically useful approach is to determine whether anomalies of particular subtelomeric regions result in an identifiable and specific phenotype, thereby directing the clinician toward the diagnosis. This strategy is simplest when there is a de novo deletion or duplication affecting only a single subtelomeric region. The most striking example is the ''1p36 deletion syndrome.'' As shown in Fig. 2(a), cases of 1p monosomy account for

Getting Started With Dumbbells

Getting Started With Dumbbells

The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.

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