Cytogenetic, clinical and genealogical analyses in a series of gonadal dysgenesis patients and their families

Phenotype/karyotype correlations of Y chromosome aneuploidy with emphasis on structural aberrations in postnatally diagnosed cases

Over 600 cases with a Y aneuploidy (other than non-mosaic 47,XYY) were reviewed for phenotype/karyotype correlations. Except for 93 prenatally diagnosed cases of mosaicism 45,X/46,XY (79 cases), 45,X/47,XYY (8 cases), and 45,X/46,XY/47,XYY (6 cases), all other cases were ascertained postnatally. Special emphasis was placed on structural abnormalities. This review includes 11 cases of 46,XYp-; 90 cases of 46,XYq- (52 cases non-mosaic; 38 cases 45,X mosaic); 34 cases of 46,X,r(Y) (9 cases non-mosaic and 25 cases 45,X mosaic); 8 cases of 46,X,i(Yp) (4 non-mosaic and 4 mosaic with 45,X); 12 cases of 46,X,i(Yq) (7 non-mosaic and 5 mosaic); 44 cases of 46,X,idic(Yq); 80 cases of 46,X, idic(Yp) (74 cases had breakpoints at Yq11 and 6 cases had breakpoints at Yq12); 130 cases of Y/autosome translocations (50 cases with a Y/A reciprocal translocation, 20 cases of Y/A translocation in 45,X males, 60 cases of Y/DP or Y/Gp translocations); 52 cases of Y/X translocations [47 cases with der(X); 4 cases with der(Y), and 1 case with 45,X with a der(X)], 7 cases of Y/Y translocations; 151 postnatally diagnosed cases of 45,X/46,XY; 14 postnatally diagnosed cases of 45,X/47,XYY; 18 cases of 45,X/46,XY/47,XYY; and 93 aforementioned prenatally diagnosed cases with a 45,X cell line. It is clear that in the absence of a 45,X cell line, the presence of an entire Yp or a region of it including SRY would lead to a male phenotype in an individual with a Y aneuploidy, whereas the lack of Yp invariably leads to a female phenotype with typical or atypical Ullrich-Turner syndrome (UTS). Once there is a 45,X cell line, regardless of whether there is Yp, Yq, or both Yp and Yq, or even a free Y chromosome in other cell line, there is an increased chance for that individual to be a phenotypic female with UTS manifestations or to have ambiguous external genitalia. This review once again shows a major difference in reported phenotypes between postnatally and prenatally diagnosed cases of 45,X/46,XY, 45,X/47,XYY, and 45,X/46,XY/47,XYY mosaicism. It appears that ascertainment bias can explain the fact that all known patients with postnatal diagnosis are phenotypically abnormal, while over 90% of prenatally diagnosed cases are reported to have a normal male phenotype. Further elucidation of major Y genes and their clinical significance can be expected in the rapidly expanding gene mapping projects. More, consequently better, phenotype/karyotype correlations can be anticipated at both the cytogenetic and the molecular level.

Study of final height in Turner's syndrome: ethnic and genetic influences

In understanding Turner's syndrome, spontaneous adult height is a prerequisite for an accurate assessment of the therapeutic efficiency of growth hormone treatment. The heights described in the literature reveal significant differences (136-147 cm). Our collaborative study pooled results from 16 pediatric endocrinology centers and obtained a large number of spontaneous adult heights (n = 216). The selective criteria were: chronological age (CA) > 18 years, bone age (BA) > 16 years, typical karyotype, no treatment with growth hormone or anabolic steroids. Mean CA was 23.3 +/- 5.6 years. Chromosomal anomalies were: monosomy X 56%; mosaicism 37.2%; structural aberration 10.6%. Mean final height in the whole group was 141.5 (129-160) cm. There was no significant difference in height between the three groups: monosomy X (n = 121: 141.1 +/- 6.4 cm); mosaicism (n = 72: 141.5 +/- 7.5 cm); X anomaly (n = 23: 141.4 +/- 5.0 cm). Mean parental height was 170.4 +/- 7.1 cm (father) and 160.1 +/- 6.2 cm (mother). Parental height and patients' heights correlated significantly, but more so with fathers' heights (r = 0.50) than with mothers' (r = 0.42). The correlation was still apparent with the target height (r = 0.55). The results of different series in the literature show the existence of significant variations as mean final heights are between 136 and 147 cm. These differences can be explained by the variations in normal female heights in each country. We have found in these different countries a very strong correlation (r = 0.91) between normal height and final height in Turner's syndrome.(ABSTRACT TRUNCATED AT 250 WORDS)

45,X/47,XYY mosaicism: clinical discrepancy between prenatally and postnatally diagnosed cases

45,X/47,XYY mosaicism is a rare chromosomal disorder with clinical information limited to 11 postnatal cases in the literature and with uncertainty regarding prenatal prediction of phenotype and prognosis. We report on 7 new cases of 45,X/47,XYY mosaicism, three detected prenatally and 4 diagnosed postnatally. A clinical comparison of the cases of 45,X/47,XYY mosaicism is presented together with a literature review.

Growth hormone treatment in girls with Turner's syndrome. A review of the literature

Most girls with Turner's syndrome seemed to increase their growth rate during the first year of growth hormone treatment. The gain is rarely more than 3 cm/year. In 3 studies the combination of growth hormone and an anabolic steroid resulted in higher growth rates compared to those with each individual compound. The results of long-term treatment (more than one year) also appear to be positive. The impact of growth hormone therapy on final height has not yet been established, however.

Turner syndrome: spontaneous growth in 150 cases and review of the literature

The spontaneous growth of 150 patients with Turner syndrome from three German centers--90 with 45,X0 constitution, 60 with other chromosomal abnormalities--has been analyzed. The mean adult height was found to be (n = 14) 146.8 cm. It was observed that growth in these patients can be divided into four phases: (1) Intrauterine growth, which is retarded; (2) Height development, which is normal up to a bone-age of about 2 years; (3) Between a bone-age of 2 and 11 years when stunting of growth is most marked; (4) After a bone-age of 11 years--the time at which puberty should normally start--the growth phase is prolonged, but total height gain is only little below normal levels. No difference in height could be observed between cases with X0 karyotype and other chromosomal variants. The data are compared with those in the literature.

Body height in Turner's syndrome

Disease-specific growth curves for Turner's syndrome were calculated by means of 2nd order homogeneous differential equations with constant coefficients, taking different cytogenetical subtypes into account. Comparison of these growth curves between X-monosomic (n = 64) and 46,XX/45,X-mixoploid (n = 20) patients reveals no differences, in contrast to the commonly accepted opinion.

Chromosomes and the gynecologist

Recent advances in cytogenetic techniques made a valuable contribution toward the modern practice of obstetrics and gynecology. The state of the art regarding the application of these techniques is reviewed in the following areas: the clinical features related to the various sex and autosomal chromosomal anomalies, the cytogenetics of gynecologic malignancies, the chromosomal analysis of spontaneous abortion and of parents with habitual abortions. Chromosome studies in male infertility revealed abnormalities in 11.5 per cent of 69 patients with azoospermia and 9.1 per cent of 165 patients with oligospermia. Among 77 patients with primary amenorrhea, 27.3 per cent revealed chromosomal abnormalities compared to 3.8 per cent in 103 patients with secondary amenorrhea. The term "ovotesticular dysgenesis" is used for the first time in the literature to describe a specific histologic type of streak gonad which contains ovarian stroma and dysgenetic testicular tubules.

Hypoplastic left heart in a patient with 45,X/46,XX/47,XXX mosaicism

Recurrence risks for primary congenital heart lesions are well defined. An infant with hypoplastic left heart syndrome is observed to have a short neck with a full skin fold on the right side, unilateral single palmar crease, and whorls on all ten fingers. She was found to have the Ullrich-Turner syndrome with mosaicism 45,X/46,XX/47,XXX. We believe the cardiac malformation was secondary to her aneuploidy. This could have important implications for prediction of recurrence risks to the parents. Chromosomal tests may be indicated for infants were severe congenital cardiac lesions, based on subtle clinical findings.

Chromosomal and clinical findings in 110 females with Turner syndrome

One hundred and ten patients with abnormal karyotypes who were referred to the Department of Medical Genetics with the possible diagnosis of Turner syndrome were reviewed. The frequency of chromosomal abnormalities and clinical findings in the different chromosomal types are summarized.