We present a patient with partial monosomy of the short arm of chromosome 18 caused by de novo translocation t(Y;18) and a generalized form of keratosis pilaris (keratosis pilaris affecting the skin follicles of the trunk, limbs and face-ulerythema ophryogenes). Two-color FISH with centromere-specific Y and 18 DNA probes identified the derivative chromosome 18 as a dicentric with breakpoints in p11.2 on both involved chromosomes. The patient had another normal Y chromosome. This is a third report the presence of a chromosome 18p deletion (and first case of a translocation involving 18p and a sex chromosome) with this genodermatosis. Our data suggest that the short arm of chromosome 18 is a candidate region for a gene causing keratosis pilaris. Unmasking of a recessive mutation at the disease locus by deletion of the wild type allele could be the cause of the recessive genodermatosis.

A small ring-shaped supernumerary marker chromosome (SMC) was detected in 50% of metaphase cells in an 18-month-old boy with mental retardation and multiple congenital anomalies. Conventional cytogenetic methods had failed to identify the origin of the marker. When the patient was age 11.5 years, we defined the origin of the SMC by fluorescence in situ hybridization using a battery of centromere-specific DNA probes. The marker was positive with the probe for locus D2Z. More detailed characterization was achieved by using chromosome 2 arm-specific and marker-specific DNA libraries, which were constructed by microdissection of the two arms chromosome 2 and SMC with subsequent amplification of the chromosomal material by a degenerate oligonucleotide-primed polymerase chain reaction (DOP-PCR). The marker was identified as r(2)(p11.2-->q14.1). The propositus had dolichocephaly, coarse hair, low-set ears, exophthalmos, epicanthal folds, strabismus, depressed nasal bridge, high-arched palate, excess of skin on the neck, tapered fingers with mild clinodactyly, talipes varus on the right, inguinal hernia, hypogenitalism, muscular hypotonia, and mental retardation. This is the first case of SMC derived from chromosome 2 that was characterized by forward and reverse chromosome painting.

Interphase fluorescent studies of X chromosome aneuploidy in cultured and uncultured blood lymphocytes and oral mucosa epithelial cells using X centromere-specific DNA probe in addition to standard karyotype analysis were performed in 50 females with a clinical suspicion of Turner syndrome. All the patients were previously screened for the presence of 'hidden' Y chromosome mosaicism, using the primers DYZ3 and DYZ. The use of fluorescence in situ hybridization (FISH) analysis of interphase nuclei of tissues from different germ layers (lymphocytes from mesoderm and buccal epithelial cells from ectoderm) improves the accuracy of detection of low-level mosaicism. FISH studies on interphase nuclei revealed that 29% of patients with a pure form of monosomy X detected by metaphase analysis are, in fact, mosaics. The level of cells with the normal chromosomal constitution in lymphocytes of these cases as a rule was low, ranging from 3 to 18%, with an average of 7%. Two false-positive cases and one false-negative case of X monosomy mosaicism determined by standard cytogenetic approach were detected using FISH analysis. The majority of patients (92%) with mosaic form of Turner syndrome have considerable tissue-specific differences in levels of X aneuploidy. Our data indicate that in cases when mosaic aneuploidy with low-level frequency is questionable (approximately 10% and lower), the results of standard metaphase analysis should be supplemented with additional FISH studies of interphase nuclei. Tissue-specific differences in contents of different cell lines in the same patients point to the necessity of studying more than one tissue from each patient.

Ангиотензин-конвертирующий фермент - металопептидаза, играющая важную роль в сосудистой физиологии, регуляции давления и электролитном балансе крови. Основной функцией АСЕ является гидролиз ангиотензина  I и конвертация его в ангиотензин II - белок, обладающий сосудосужающим действием и регулирующий рост гладкомышечных клеток сосудов и кардиомиоцитов. АСЕ также  способен инактивировать брадикинин, отщепляя от его молекулы два карбокситерминальных дипептида, Брадикинин является потенциальным вазодилятором, а также ингибирует рост гладкомышечных клеток сосудов. Таким образом, индуцируя производство ангиотензина II и деградацию брадикинина, АСЕ потенциально является фактором, способствующим сужению сосудов, пролиферации сосудистых клеток и перестройке артериального русла. 

На основании выборочного анализа актов регистрации браков за два временных периода (1970— 1972 и 1985—1990 гг.) проведено изучение структуры браков по национальностям и местам рождения супругов с оценкой показателей ассортативности, а также индексов миграции и эндогамии в г. Томcке. Показано, что за анализируемый временной интервал имела место отчетливая динамика изуxенных показателей генетико-демографической структуры. Она заключалась в возрастании индекcа эндогамии и снижении индекса миграции и в не менее отчетливом снижении индексов брачной ассортативности. Данное обстоятельство может быть интерпретировано как стабилизация во времени генетической структуры и уменьшение степени внутрипопуляционной подразделенности (приближение к панмиксии) для урбанизированной популяции г. Томска.