263 results match your criteria: "The Genetics Institute[Affiliation]"

Phylogeny of seed plants based on evidence from eight genes.

Am J Bot

October 2002

Department of Botany and the Genetics Institute, University of Florida, Gainesville, Florida 32611-5826 USA;

Article Synopsis
  • Relationships among the five groups of extant seed plants (cycads, Ginkgo, conifers, Gnetales, and angiosperms) are still unclear, prompting researchers to analyze a comprehensive data set of genes from these plants to resolve conflicting molecular data.
  • The study utilized a combined set of eight genes from cpDNA, mtDNA, and nuclear DNA across 19 representative species, revealing that gymnosperms form a clade closely related to angiosperms, with Gnetales appearing to be closely related to conifers.
  • Significant discrepancies in the evolutionary relationships were noted depending on the specific analyses used, particularly with the third codon positions of cpDNA, leading to different conclusions about Gnetales' position among
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We report on a 'new' lethal familial short-limb bone dysplasia associated with multiple anomalies in three sibs born to Arabic-Muslim consanguineous healthy parents. Clinical abnormalities included short limbs and short hands, cloverleaf skull, frontal bossing, wide anterior fontanel, hypertelorism, bilateral microphthalmia, cataract, low-set ears, narrow chest, ambiguous genitalia, cardiac ventricular septal defect (VSD) and agenesis of the corpus callosum. Radiological abnormalities included cloverleaf skull, hypoplastic clavicles and scapulae, thin, wavy cupped ribs, flat vertebral bodies with coronal clefting and several unossified vertebral pedicles and hypo-ossification of the pubic bone.

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Many efforts to date evolutionary divergences by using a molecular clock have yielded age estimates that are grossly inconsistent with the paleontological evidence. Such discrepancies often are attributed to the inadequacy of the fossil record, but many potential sources of error can affect molecular-based estimates. In this study, we minimize the potential error caused by inaccurate topology and uncertain calibration times by using a well-supported tree, multiple genes, and multiple well-substantiated dates to explore the correspondence between the fossil record and molecular-based age estimates for major clades of tracheophytes.

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Real-time and color Doppler ultrasound were used to examine 103 second trimester fetuses with abnormal chromosomes (trisomies 13, 18, 21 and sex aneuploidy =86; other =17) and 2000 controls from women of advanced maternal age who electively underwent genetic amniocentesis. Ten ultrasound markers were analyzed and likelihood ratios were computed for each abnormal ultrasound finding and for a normal ultrasound study if none of the ten markers were present. Abnormal ultrasound markers were present in 81% of fetuses with abnormal karyotypes.

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We describe a newborn girl with a lethal sclerosing bone dysplasia leading to prenatal skeletal alterations and microcephaly, proptosis, hypoplastic nose and midface, small jaw, cleft palate, hypertrophied gums, intracranial calcifications, and generalized osteosclerosis. There is a remarkable similarity between our patient and six previously reported infants subsequently categorized as having a distinct entity: Raine syndrome. Autosomal recessive inheritance is postulated based on parental consanguinity in several of the previous cases and in our patient.

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Stable centromeric breakage in non-acrocentric chromosomes and balanced reciprocal translocation mosaicism are both rare events. We studied a family in which the mother had mosaicism for a balanced reciprocal translocation between chromosomes 10 and 16 which was associated with a break in chromosome 16 centromere alpha-satellite DNA ¿146,XX,t(10;16)(q11.2;q11.

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The impact of prenatal detection of congenital heart defects (CHD) using the four-chamber screening examination cannot be accurately ascertained because of the wide range of detection rates that affect the cost associated with it. Assuming a screening ultrasound cost of $200 per examination, recent studies in which examiners not trained in fetal echocardiography obtained and interpreted the four-chamber view only identified 5.3% of CHD, for a cost of $476,190 per malformation.

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Monosomy of the entire short arm of chromosome 18 as a result of an 18;acrocentric whole arm translocation has been reported in over 20 patients, 3 of which were familial. The centromeric origin in de novo cases has not been characterized. We report molecular cytogenetic studies of two prenatally-detected de novo cases.

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We report on a 30-year-old women with de novo ring chromosome 12 mosaicism, 46,XX, r(12)(p13.3q24.3)/46,XX.

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The objective was to describe a technique using color Doppler to identify the outflow tracts of the fetal heart by directing the ultrasound transversely through the fetal chest. One hundred second- and third-trimester control fetuses were examined with real-time and color Doppler ultrasound. The ultrasound beam was directed cephalad, in the same transverse plane used to image the four-chamber view, and the outflow tracts were examined.

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The aim of the study was to determine whether color Doppler identifies abnormal fluid within the pericardial space of the fetal were referred for heart. Second- and third-trimester fetuses diagnostic ultrasound. The four-chamber view of the fetal heart was imaged with real-time ultrasonography and examined for the presence or absence of separation of the pericardium from the epicardium, which extended from the atrioventricular junction toward the apex of the ventricle.

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Fetal echocardiography and a detailed non-cardiovascular ultrasound examination were performed prospectively between 14 and 23 weeks of gestation prior to genetic amniocentesis in 2800 consecutive fetuses at increased risk for trisomy 21 due to advanced maternal age or a low maternal serum alpha-fetoprotein. An abnormal nuchal skin fold was defined as >or=6 mm. Of 2800 fetuses, 23 (0.

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This study was designed to examine ventricular preload by measuring the ductus venosus index during the second trimester of pregnancy. A total of 137 women were entered into the study. Each fetus was examined with real-time, color and pulsed Doppler ultrasound.

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