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We report on a de novo interstitial deletion of 20q11.21–q11.23 in a 2-year-old girl with a set of dysmorphic features, cleft palate, heart defect, severe feeding problems, failure to thrive, developmental delay, preaxial polydactyly (right thumb), and retinal dysplasia. Interstitial microdeletions of the long arm of chromosome 20 are rare. Exclusively rare are proximal microdeletions involving 20q11–q12 region. Our patient is the fourth described so far and has the smallest deleted region 20q11.21–q11.23 of 5.7 Mb. The defined clinical phenotype of our patient is very similar to previously published cases and confirms the existence of retinal dysplasia and skeletal abnormalities as a part of phenotypic spectrum for deletion 20q11–q12. Description of four similar patients, including two almost identical, suggests a new distinct, phenotypicaly recognizable microdeletion syndrome associated with the loss of 20q11–q12 region. © 2014 Wiley Periodicals, Inc.

We performed the segregation analysis of a relatively large pedigree of t(7;13)(q34;q13) carriers together with the sperm karyotype analysis of the one carrier using a tri-color fluorescence in situ hybridization (FISH) method. The risk assessments for unfavorable pregnancy outcomes in a series of 36 pregnancies in eight reciprocal chromosome translocation (RCT) couples of carriers were estimated directly from a pedigree after ascertainment correction. The individual probability rate for unbalanced child was predicted according to Stengel-Rutkowski and co-workers. The unbalanced karyotypes in the form of monosomy 7q34-->qter and trisomy 13q13-->qter were detected among stillborn/early death newborns with holoprosencephaly (HPE), cyclopia and other malformations. Based on clinical description of unkaryotyped stillbirth progeny, it can be assumed that the phenotype distinctions were connected with the unbalanced karyotype from 2:2 segregation (monosomy 7q with trisomy 13q) and 3:1 segregation as interchange trisomy 13 (Patau syndrome). Probability rates for miscarriages, stillbirth/early death were 12.9 +/- 6% (4/31) and 29 +/- 8.2% (9/31), respectively. The results of the meiotic segregation pattern indicated the rate of unbalanced spermatozoa for about 60%, with the unusual high rate (29.4%) of 3:1 segregant (i.e., 13.4% of the tertiary segregation and 16% of the interchange segregation). Adjacent-1 segregation followed with 23.5% and adjacent-2 followed with 7.2% of analyzed spermatozoa. The high rate of unbalanced gametes in comparison to the number of stillborn/early death and miscarriages detected in pedigree suggests a strong selection against unbalanced chromosomal constitutions during fetal development. It corresponds to a very small probability rate (about 0.3%) of viable unbalanced progeny from 3:1 meiotic segregation predicted for maternal carriers. This knowledge can be used in genetic counseling of families with similar RCT ascertained in a different way.

Mobius syndrome (OMIM#157900) is an extremely rare congenital entity involving bilateral or unilateral palsy of the facial nerve, usually with dysfunction of other cranial nerves (second, third, fifth, sixth, ninth, tenth and twelfth). It was estimated that Mobius syndrome occurs in 1 of 50 000 live births. The aetiology and the pathogenesis of the syndrome remain unknown. The majority of published cases were sporadic. We report on the natural history of a 32-year-old man with de novo Mobius syndrome. The diagnosis was established at the age of 9 months due to partial bilateral facial and abducent nerve palsy. Additionally, the patient demonstrated failure to thrive during infancy and childhood, many dysmorphic features, lower limb anomalies, and hypogonadism in adulthood, but his intelligence was in the normal range. The low quality of life of the patient with Mobius syndrome is emphasized.

We report on a 27-year-old man, who represents the sixth and the youngest published case of Primrose syndrome. Primrose syndrome (PS) (OMIM#295090) is an extremely rare entity of unknown etiology characterized by the progressive wasting of distal muscles of the legs, the small muscles of the hands resulting in contractures, the presence of intellectual disability, hearing problems, cataracts, brain calcification, and the ossification of ear cartilage. All the main manifestations were present in our patient. Despite the phenotypic similarity to five other cases, our patient had mild intellectual disability. Additionally we found hypergonadotropic hypogonadism and a low bone density due to progressive osteoporosis. We discuss our observations in relation to previously published cases, and we stress the need for the detail and phenotypic descriptions of further cases as PS remains rare, and the genetic basis is still undiscovered.

The main aim of this work is to present unusual case with full trisomy 18 and additional robertsonian translocation- Rob (13;14) detected through abnormalities found in prenatal ultrasound examination. A 26 years-old pregnant women with no family history of any reproductive failure underwent level II ultrasound screening in 19 weeks of gestation. Polyhydramnios, intrauterine growth retardation, hydrocephalus, enlarged lateral ventricles, club foot and cardiac defect were found. Amniocentesis was indicated considering the high likelihood of a chromosomal aberration. Abnormal karyotype was detected 46, XY, der(13;14)(q10;q10), +18. Karyotypes of parents were normal, what confirmed de novo origin of this aberration. Pregnancy was terminated. In postnatal examination fetus demonstrated intrauterine groth retardation and a lot of dysmorphic features characteristic for trisomy 18: microcephaly, prominent occiput, very low set and posteriorly rotated ears, hypertelorism, small mouth, small recessed mandible, a high narrow palate, broad nasal bridge, low-set ears, preauricilar skin appendage, clenched fingers clinodactyly of Vth fingers and club foot. In conclusion it is worth to say that our described fetus demonstrated rather typical for trisomy 18 ultrasonographic features. Balanced Rob (13;14) gives no phenotypic expression. Possible interchromosomal effect in complex chromosomal aberration formation such as Rob (13;14) with trisomy 18 was discussed.

Purpose: Genetic counseling of carriers with individual chromosome translocation requires information on how balanced reciprocal chromosome translocations (RCT) will segregate, what possible form of unbalanced embryo/fetus/child can occur, and the survival rates that have been observed in the particular families. We collected new empirical data and evaluated pedigrees of RCT carriers involving 9p in order to improve risk figures. Material and Methods: Empirical data on 241 pregnancies of 70 carriers were collected from 32 pedigrees of carriers of RCT at risk for a single 9p segment imbalance (RCT9p) from the literature and unpublished data. The probability rates of particular types of pathology have been calculated according to the method of Stengel-Rutkowski and Stene. Cytogenetic interpretation was based on GTG, RBG and FISH techniques. Results: The probability rate for unbalanced offspring at birth for the whole group of pedigrees was calculated as 17.8±3% (33/185) (high risk). Considering the size of the imbalanced segment of 9p, the probability rates for RCT carriers with a breakpoint position at 9p22 at 9p13 and at 9p11.2 were estimated separately, and were found as 21.2±4.4% (18/85), 25±8.8% (6/24) and 11.8±3.7% (9/76), respectively. For unbalanced fetuses at 2nd prenatal diagnosis, we found the risk value as 57.9±11.3 % (11/19). The risk value for unkaryotyped stillbirths/early deaths of newborns and miscarriages were 5.4±1.7% (10/185) (medium risk) and 13±2.8% (rate 24/185) (high risk) respectively. Conclusions: Our results showed that the recurrence probability rates are different for particular categories of unfavorable pregnancy outcomes. How much they are dependent on the size of 9p chromosome segments taking part in the imbalance needs further studies based on a larger number of observations.