[The inclusion of new techniques of chromosome analysis has improved the cytogenetic profile of Turner syndrome]

Growth charts of Brazilian girls with Turner syndrome without the use of GH or oxandrolone

OBJECTIVE

The development of specific growth charts for Turner Syndrome (TS) promotes adequate assessment of growth and weight gain, and earlier diagnosis of comorbidities, and may help to analyze the effectiveness of treatments to promote growth and puberty. The aim of this study was to construct a growth chart with the largest possible series of patients with a cytogenetic diagnosis of TS from a Brazilian reference center.

METHODS

This is a longitudinal study, with 259 cases of TS born between 1957 and 2014 and followed between 1975 and 2019, without the use of GH or oxandrolone. 3,160 height measurements and 2,918 wt measurements were used, with subsequent calculation of the Body Mass Index (BMI). For data analysis, the "GAMLSS" package of the "R" software was used.

RESULTS

The mean target height was 157.8 cm (standard deviation 5.2; median 160.4 cm). The mean height of patients with TS at 20 years of age was 145.6 cm (standard deviation 5.9; median 146.7 cm). Height, weight, and BMI by age graphs were developed for TS girls between 2 and 20 years.

CONCLUSION

These growth charts may be used to monitor the growth of girls with TS and to verify the effect of adjuvant treatments on promoting growth.

Can Individuals with 47,XYY Karyotypes Exist without Male Phenotype? A Narrative Literature Review and Case Report

BACKGROUND

The 47,XYY syndrome is a genetic condition found in about 1 in 1000 male children. The expected phenotype is male but could vary greatly. Those with genitourinary abnormalities may also present with microphallus, hypoplastic scrotum, cryptorchidism, hypospadias and macroorchidism. This study reports a child with sex ambiguity who possesses an initial 47,XYY karyotype. We also conducted a narrative literature review of 47,XYY individuals and their respective genital phenotype and/or gender identity.

METHODS

The narrative literature review was performed by searching for "47,XYY" in the PubMed database. All studies published in English, Spanish or Portuguese from January 1960 to January 2024 that contained the term "47,XYY" in the title or abstract were included. Studies that did not describe the genital phenotype and/or gender identity of cases were excluded. We also described the case of a 2-month-old patient with the 47,XYY karyotype and sex ambiguity.

RESULTS

Our patient underwent additional karyotype testing, resulting in 47,XYY [30] and another 45,X [2]/47,XYY [98] with mosaicism being confirmed by fluorescent in situ hybridization (FISH) on buccal smears (nuc ish (DXZ1 × 1, DYZ3 × 2)[64/100]/(DXZ1 × 1, DYZ3 × 0)[36/100]. A gonadal biopsy revealed an atrophic testis on the left and a streak gonad on the right, with a final diagnosis of mixed gonadal dysgenesis determined. The narrative review revealed 643 articles, of which 350 met the inclusion criteria. However, we excluded 132 articles because they presented no new cases. We included 138 articles, which presented a series containing less than 10 new cases with the 47,XYY karyotype (total of 327 cases), 58 articles presented 4001 cases and 22 articles presented 75 patients with the 47,XYY karyotype in mosaic with 45,X. For all 4403 analyzed cases, 4354 (98.90%) presented a male phenotype, of which 4322 had the 47,XYY karyotype and 32 had mosaicism with 45,X lineage. A further 23 (0.52%) presented a female phenotype, of which four had the 47,XYY karyotype and 19 had mosaicism with 45,X lineage. In addition, 23 (0.52%) cases presented ambiguous genitalia, of which two had the 47,XYY karyotype and 21 had mosaicism with 45,X lineage. Finally, three (0.06%) cases had undefined phenotypes, all with mosaicism with 45,X lineage. Of the six cases with the 47,XYY karyotype and no male phenotype, one had complete androgen insensitivity syndrome (CAIS), one had lipoid congenital adrenal hyperplasia, two had probable CAIS, and two presented an incomplete diagnostic investigation.

CONCLUSIONS

A female or ambiguous genital phenotype in an individual with 47,XYY karyotype is uncommon and should alert to the presence of the 45,X lineage or association with other causes of disorder/difference of sex development.

Efferent Auditory Pathways Inhibition in Turner syndrome

PURPOSE

The goal of this study is to investigate the efferent auditory pathways inhibition in Turner's syndrome and to relate it to the cytogenetic profile.

METHODS

This is a cross-sectional study with a comparison group. A sample with 94 participants divided into two groups: The study group was a sample of 40 patients diagnosed with Turner's syndrome (17.6 years of age). The control group was composed of 54 volunteers (18.9 years of age), female, without syndrome. The selected individuals were submitted to efferent auditory pathways inhibition research.

RESULTS

The mean of the inhibitory effect of the efferent auditory pathway in the study group in the right ear was 0.4 dB and in the comparison group it was 1.9 dB, however in the left ear the mean of the inhibitory effect of the efferent auditory pathway was 1.4 dB in the study group and 0.8 dB in the comparison group. The inhibitory effect of the efferent auditory pathway was present in 14 individuals with monosomy and in 15 with other cytogenetic alterations.

CONCLUSIONS

In the study group, the efferent auditory pathways inhibition value was significantly higher in the left ear and significantly lower than the control group in the right ear. There was no significant difference in efferent auditory pathways inhibition of right ear and left ear between the karyotype types.

Identification of Y-Chromosome Sequences in Turner Syndrome

OBJECTIVES

To investigate the presence of Y-chromosome sequences and determine their frequency in patients with Turner syndrome.

METHODS

The study included 23 patients with Turner syndrome from Brazil, who gave written informed consent for participating in the study. Cytogenetic analyses were performed in peripheral blood lymphocytes, with 100 metaphases per patient. Genomic DNA was also extracted from peripheral blood lymphocytes, and gene sequences DYZ1, DYZ3, ZFY and SRY were amplified by Polymerase Chain Reaction.

RESULTS

The cytogenetic analysis showed a 45,X karyotype in 9 patients (39.2 %) and a mosaic pattern in 14 (60.8 %). In 8.7 % (2 out of 23) of the patients, Y-chromosome sequences were found. This prevalence is very similar to those reported previously. The initial karyotype analysis of these patients did not reveal Y-chromosome material, but they were found positive for Y-specific sequences in the lymphocyte DNA analysis.

CONCLUSION

The PCR technique showed that 2 (8.7 %) of the patients with Turner syndrome had Y-chromosome sequences, both presenting marker chromosomes on cytogenetic analysis.

New approach to phenotypic variability and karyotype-phenotype correlation in Turner syndrome

BACKGROUND

Phenotypic variability of Turner syndrome (TS) challenges clinicians, and undiagnosed mosaicism may lead to conflicting results of karyotype-phenotype correlations. This study assessed the extent of phenotypic variability and investigated the presence of karyotype-phenotype correlations.

METHODS

The sample comprised 80 patients with ≥50 cells analyzed in karyotype. Twenty were 45,X/46,X,+mar; three groups of 20 patients were constructed by matching those girls with the nearest-aged patient with 45,X, 45,X/46,XX and 45,X/46,X,i(Xq) or 46,X,i(Xq) karyotype.

RESULTS

Data were obtained on height z-score, dysmorphic features, echocardiogram and urinary system sonography. The number of dysmorphic features ranged from one to 16 and was not correlated to age at diagnosis or height. The groups did not differ in height, number of dysmorphic features, cardiovascular and urinary system anomalies and frequency of any specific feature, except for short fourth metacarpal.

CONCLUSIONS

Wide phenotypical variability of TS may be objectively described and its clinical picture is not correlated to karyotype.

[Prevalence of Y-chromosome sequences and gonadoblastoma in Turner syndrome]

OBJECTIVE

To assess the prevalence of Y-chromosome sequences and gonadoblastoma in patients with Turner syndrome using molecular techniques.

DATA SOURCE

A literature search was performed in Pubmed, limiting the period of time to the years 2005 to 2014 and using the descriptors: Turner syndrome and Y sequences (n=26), and Turner syndrome and Y-chromosome material (n=27). The inclusion criteria were: articles directly related to the subject and published in English or Portuguese. Articles which did not meet these criteria and review articles were excluded. After applying these criteria, 14 papers were left.

DATA SYNTHESIS

the main results regarding the prevalence of Y-chromosome sequences in Turner syndrome were: 1-about 60% of the studies were conducted by Brazilian researchers; 2-the prevalence varied from 4.6 to 60%; 3-the most frequently investigated genes were SRY, DYZ3 and TSPY; 4-seven studies used only PCR, while in the remaining seven it was associated with FISH. Nine of the 14 studies reported gonadectomy and gonadoblastoma. The highest prevalence of gonadoblastoma (33%) was found in two studies. In five out of the nine papers evaluated the prevalence of gonadoblastoma was 10 to 25%; in two of them it was zero.

CONCLUSIONS

according to these data, molecular analysis to detect Y-chromosome sequences in TS patients is indicated, regardless of their karyotype. In patients who test positive for these sequences, gonadoblastoma needs to be investigated.

[Turner syndrome and genetic polymorphism: a systematic review]

Objective:

To present the main results of the literature on genetic polymorphisms in Turner syndrome and their association with the clinical signs and the etiology of this chromosomal disorder.

Data sources:

The review was conducted in the PubMed database without any time limit, using the terms Turner syndrome and genetic polymorphism. A total of 116 articles were found, and based on the established inclusion and exclusion criteria 17 were selected for the review.

Data synthesis:

The polymorphisms investigated in patients with Turner syndrome were associated with growth deficit, causing short stature, low bone mineral density, autoimmunity and cardiac abnormalities, which are frequently found in patients with Turner syndrome. The role of single nucleotide polymorphisms in the etiology of Turner syndrome, i.e., in chromosomal nondisjunction, was also confirmed.

Conclusions:

Genetic polymorphisms appear to be associated with Turner syndrome. However, in view of the small number of published studies and their contradictory findings, further studies in different populations are needed in order to clarify the role of genetic variants in the clinical signs and etiology of the Turner syndrome.

Frequency and types of chromosomal abnormalities in Turkish women with amenorrhea

STUDY OBJECTIVE

To estimate the frequency and the type of chromosomal abnormalities (CA) in patients with primary (PA) and secondary amenorrhea (SA).

DESIGN

This retrospective study was comprised of patients had been referred to our laboratory between 1990 to 2008 and designed as original article.

SETTING

Medical Faculty of Cukurova University in Turkey.

PARTICIPANTS

Chromosomal analysis was carried out on 393 patients with PA and SA that were referred to Cytogenetic laboratory of Medical Biology and Genetic Department, Faculty of Medicine, Çukurova University.

INTERVENTIONS

Lymphocyte culturing depended karyotyping.

MAIN OUTCOME MEASURES

Standard lymphocyte culturing procedure and karyotyping was performed to all samples.

RESULTS

PA and SA were identified in 393 patients. The karyotype was normal in 337 cases (85.8%) and abnormal in 56 (14.2%) patients. CAs were found in 54 (13.7%) and 2 (0.5%) of women with PA and SA, respectively. Females carrying rearrangements between autosomal and sex chromosomes were detected in 2% (8/393). The numerical abnormalities of the X chromosome were detected in 39.3% (22/56) (monosomy and mosaic). Structural abnormalities of the X and the other chromosomes were detected in 25.5% (13 of 56). Structural mosaicism of X chromosome was found in 5.4% (3 of 56). Male karyotype (46, XY) was found in 33.9% (19/56). The most frequently detected abnormality were X chromosome monosomies or mosaics.

CONCLUSIONS

Our study revealed that some causes of amenorrhea could be due to CAs. Therefore, cytogenetic study should be important test in the evaluation of patients with PA or SA. The most common abnormality seen is 45,X karyotype (monosomy X/Turner Syndrome) and its variants.

Growth curves for girls with Turner syndrome

The objective of this study was to review the growth curves for Turner syndrome, evaluate the methodological and statistical quality, and suggest potential growth curves for clinical practice guidelines. The search was carried out in the databases Medline and Embase. Of 1006 references identified, 15 were included. Studies constructed curves for weight, height, weight/height, body mass index, head circumference, height velocity, leg length, and sitting height. The sample ranged between 47 and 1,565 (total = 6,273) girls aged 0 to 24 y, born between 1950 and 2006. The number of measures ranged from 580 to 9,011 (total = 28,915). Most studies showed strengths such as sample size, exclusion of the use of growth hormone and androgen, and analysis of confounding variables. However, the growth curves were restricted to height, lack of information about selection bias, limited distributional properties, and smoothing aspects. In conclusion, we observe the need to construct an international growth reference for girls with Turner syndrome, in order to provide support for clinical practice guidelines.