tl_files/tiny_templates/Bilder TL/Header-sSMC.jpg

- sSMC -

X-CHROMOSOME

References

 

             
  Cases without
clinical findings
6 Cases with
clinical findings
30 symptoms  
  similar imbalances - no clinical findings similar imbalances with clinical findings  
    'Turner syndrome'
with 46,X,der(X)
   
  Cases with
unclear clinical correlation
Cases with
neocentromeres
2 tumor
0
 
  similar imbalances  
      DISCLAIMER      

In general 70% of sSMC carriers are clinically normal. The figures here
are based on the bias, that mainly clinically aberrant cases are reported in literature!

           
  UPD (uniparental disomy) cases: UPD X
mat
UPD X
pat
UPD X
unclear
 
           

 


the probably non-dosage sensitive pericentric region of X-chromosome


SCHEMATIC CYTOGENETIC DEPICTION

tl_files/tiny_templates/Bilder TL/sSMC/sSMC-X.jpg



SCHEMATIC MOLECULARGENETIC DEPICTION

acc. to UCSC Genome Browser on Human Mar. 2006 assembly [UCSC hg18, 2006]
and available BAC-data/ array-data from cases marked *** mentioned below [MB]

critical region 50.90 --- 56.60 uncritical region [56.60 centromere 65.10] uncritical region 65.10 --- ? critical region

Below adapted for UCSC hg19, 2009

critical region 50.91 --- 58.10 uncritical region [58.10 centromere 64.60] uncritical region 64.60 --- ? critical region

 


Clinical symptoms of centromere-near proximal imbalances

 

chromosomal region

Xp - proximal Xq - proximal
symptoms
developmental delay 75 % -
dysmorphic face 65 % -
finger or toe/foot malformations 50 % -
hypotonia 50 % -
obesity 75 % -
ocular problems 25 % -
seizures 25 % -
number of cases (marked with “°” below) 4
0
 

References

Cases without clinical findings (O)

 

 
  case no. gender/
age at diagnosis
studied
material
de novo/
inherited
GTG-banding result
grade of mosaicism
final result of the sSMC test
methods
clinical symptoms reference  
  ***
0X-O-
p11.1/

1-1
***
female/
prenatal
PL; PBL de novo see below min(X)(:p11.1q11:) cenM; subcenM; UPD-test nuchal translucency in ultrasound; child born without any abnormal clinical signs {1} case 2
{2} case 2
{3} case 9
{4} case 9
 
PL: 47,XX,+mar[15]/46,XX[8]
PBL:
47,XX,+mar[13]/46,XX[2]
  ***
0X-O-
p11.1/

1-2
***
female/
prenatal
AF de novo 47,XX,+mar[100%] min(X)?(:p11.1q11:) cep X; XIST detected during prenatal rapid FISH-test; no ultrasound abnormalities; normal child born {24} case 1  
  ***
0X-O-
p11.1/

1-3
***
female/
22y
PBL de novo 47,XX,+mar[100%] min(X)?(:p11.1q11:) cenM subcenM
normal female {0} provided by Dr. P. Lonsky, Prague, Czech Rep.  
                     

 

O-Cases with similar imbalances NOT caused by sSMC (O-IMB)

none reported yet

 

O-cases with unclear/insufficient characterization of the sSMC (CO):

 

 
  case no. gender/
age at diagnosis
studied
material
de novo/
inherited
GTG-banding result
grade of mosaicism
final result of the sSMC test
methods
clinical symptoms reference  
  0X-
CO-1
female/
prenatal
AF/PBL de novo 47,XX,+r[2%]/
46,XX[98%]
mar present in 1.1% of PBL and 2.5% of fetal membrane
r(X)
(it is stated in text that Xq13 might be included)
all available centromeric probes; wcpX normal at birth {12} case 37  
  0X-
CO-2
male/
prenatal
AF/PBL de novo 47,XY,+mar[100%] min(X).ish (DXZ1+) all available centromeric probes Amniocentesis due to anxiety; normal at birth {23} case 2  
  0X-
CO-3
male/
prenatal
AF/PBL de novo 47,XY,+mar[6]/46,XY[17]
(AF: 15th week of gestation)
47,XY,+mar[2]/46,XY[30]
(AF: 21th week of gestation)
47,XY,+mar[6]/46,XY[18]
(PBL: 5 weeks after birth)
r(X)
.ish (DXZ1+,XIST-)
SKY, XIST Amniocentesis due to abnormal maternal serum screening result - Down syndrome risk 1:138; normal at birth and 1 y {28}  
                     

 


References

Cases with clinical findings (W)

 

 
  case no. gender/
age at diagnosis
studied
material
de novo/
inherited
GTG-banding result
grade of mosaicism
final result of the sSMC test
methods
clinical symptoms reference  
  0X-W-
p21/
2-1
see McCl-0X-W-p21/2-1
{19}  
  0X-W-
p11.?3/
1-1
male/
postnatal
PBL n.a. 47,XY,+mar[100%] min(X)(:p11.?3q11.1:)[1]/
min(X)(:p11.1
q11.1:)[2]/
min(X)(p11.2?2
q11.1:
:q11.1
p11.1:)[4]/
min(X)(:p11.1~q11.1:
:q11.1
p11.1:)[6]
CGH, HR-CGH; subcenM multiple malformations {41}  
  0X-W-
p11.3/
1-1
male/
prenatal
CVS; PBL de novo 47,XY,+mar[9]/
46,XY[11]
r(X)(::p11.3q13.1::)
included in sSMC: RP11-386N14 (44.54 MB) to RP11-446J19 (68.63 MB); XIST not included
array CGH see below {42}  
In pregnancy in week 12 a cystic hygroma was noted in the fetus. Normal growth until week 32, then mild IUGR. At birth weight 2.27 kg (3rd percentile) length 45cm (10th percentile). Unusual facial features, limb anomalies, and undescended testicles. Neonatal problems: initial low blood glucose and poor temperature regulation. At day 5 sent home in good condition. With 2 months poor weight gain, slow feeding with poor caloric intake, and hypotonia. All growth parameters <5th percentile for age, very wide midface, bifid flame nevus on his forehead, hypertelorism, epicanthal folds, mild proptosis with shallow orbits, roving eye movements but intact extraocular movements, bifid and upturned nasal tip, and anteverted nares, ears low set and posteriorly rotated with simplified helices and pits on both lobes, mouth small and asymmetric with apparent intact orbicularis oris muscle function and no facial palsy; Oral cavity revealed a high-arched palate without clefting and a prominent median lingual frenulum; mild pectus excavatum, hypospadias with normal-sized phallus and bilateral cryptorchidism, shallow sacral dimple, and a narrow but patent anus, limb anomalies that included broad thumbs, bilateral 3,4 cutaneous syndactyly, normal palmar creases, and distal limb asymmetry. The left foot had a broad great toe which deviated medially and 3,4 syndactyly; right foot 2,3 syndactyly and a normal great toe. Skin examination was pertinent for whorls and streaks of hyperpigmentation over trunk, flame nevus. Abdominal ultrasonography: single left kidney and patent ductus arteriousus (deemed hemodynamically insignificant at that time). Magnetic resonance imaging of brain: small anterior body of the corpus callosum with absence of the posterior body, splenium, and rostrum and a prominent, high-riding third ventricle; radiograph of the upper gastrointestinal tract showed severe gastroesophageal reflux; subsequently found to have vesicoureteral reflux and was admitted to the hospital at the age of 8 months for urologic surgery including exploratory cystoscopy, ureter reimplantation, bilateral orchidopexy with inguinal hernia repair, and release of chordee tendinae. A presumed ectopic ureter entering the bladder neck near the verumontanum with no renal attachment was noted and removed. Pathologic evaluation revealed that this tissue was in fact a rudimentary cervix and uterus with bilateral fallopian tubes. No ovarian structures were noted. He underwent a respiratory arrest a few days after surgery and had a complicated hospital course requiring prolonged ventilator support. At 1 year (Fig. 1B) at which time he was noted to have similar physical features to his previous evaluation at the age of 2 months. He was making slow developmental progress and gaining some new skills.
  0X-W-
p11.22/
1-1
male/
3y
PBL de novo 47,XY,+mar[22]/
46,XY[8]
min(X)(:p11.22q11.1~11.2:)* SKY, locus specific probes, array CGH see below {29}  
Patient at birth 2920g, 47cm long and OFC 34.1cm. At 3y mental retardation, speech delay, height 96.7cm, hyperactivity, no speech, hypertelorism, arched eyebrows, epicantal folds, low-set ears, short nose, depressed nasal tip, long philtrum, small mouth, clinodactyly of both 5th fingers, syndactyly of left second and third toes.
  ***
0X-W-
p11.22/
1-2 °
***
female/
3y
PBL de novo 47,XX,+mar[30] min(X)(:p11.22q11.1:)*
distal breakpoint in Xp: 50.9MB
SNP 250 K Nsp GeneChip array (Affymetrix) see below {39}  
Normal pregnancy. Birth weight 2,750 g (10th centile), length 49 cm (50th centile), head circumference 33.5 cm (25th centile). Mild hypertelorism at birth. At 12 months hypotonia and global developmental delay; first walked at age 21/2 years. At age 3 years had no distinguishable words, but able to follow simple instructions, feed herself with finger-food and hold a cup with two hands. There was no developmental regression; weight 16.3 kg (95th centile), length 92.4 cm (25th centile), and head circumference 47 cm (25th centile). Facial features: broad forehead, hypertelorism, down slanting palpebral fissures, prominent and anteverted alar nasae, prominent nasolabial groove, thin vermillion border, and low set ears, disorganized dentition and an intact palate; genu valgum and bilateral single palmar creases, with short fingers and tapering thumbs, short great toes and 4th toe clinodactyly. Genitalia and anus were normal. She was hypotonic but her neurological examination was otherwise normal.
0X-W-
p11.22/
2-1
male/
9y
PBL n.a. 47,XY,+mar[8]/
46,XY[7]
r(X)(::p11.22q12::) ceps,
subcenM
PCeR-FISH
DD, facial dysmorphisms {0} provided by Dr. Küchler, Essen, Germany
  0X-W-
p11.21/
1-1 °
male/
13y
PBL n.a. 47,XY,+mar[100%] FISH: min(X)(:p11.21q10:)[4]/
min(X)(:p11.21
q10:
:q10
p11.21:)[8]/
r(X)(::q10
p11.21:
:q10
p11.21::)[2]
aCGH revised: 55,652,680-64,349,995 MB
cenM; subcenM; array CGH Patient with non-specific mild-to-moderate mental retardation, with a normal phenotype, except for some hypotonia. The parents also have a mental handicap. {27}case X-1;
{31} case C
 
  0X-W-
p11.21/
2-1 °
female/
11y
PBL/ Fibroblasts de novo 47,XX,+mar[40]/
46,XX[8]
25/13 in fibroblasts}
min(X)(:p11.21q11.1:)* all available centromeric probes; wcpX; 7 pericentric probes as specified in {22} see below {22} case 2  
Pregnancy was complicated by hypertension, delivery normal. Birth weight 2,400 g; length 48 cm. She developed grave hyperbilirubinemia and had an exchange transfusion. Poor feeding present in neonatal period. Failure to thrive until age 6 months followed by increasing weight gain and obesity after 3 years, which has persisted. At 3 years myopia (-10 diopt.) was noted. At years was found to be severely retarded with a developmental age of approximately 3 years. At age 20 years, a seizure occurred and EEG was found to be abnormal. She was assessed by a psychiatrist due to regression as well as aggressive and impulsive behavior => Atypical mood disorder. Behavior always restless and unfocused, sometimes aggressive. Pubertal development was normal. Minor anomalies include hypertelorism, small nose, epicanthus, low hairline in the neck, ‘‘carp-shaped’’ mouth, lordosis, genua valga, small hands, and small feet. Deletion in the Prader-Willi critical region (15q11) was excluded by FISH
  0X-W-
p11.21/
3-1 °
female/
1y
PBL de novo 47,XX,+mar[60%]/
46,XX[40%] acc. to {9}
66%/34% acc. to {22} 
min(X)(:p11.21q11.2:)* all centromeric, wcpX; 7 pericentric probes as specified in {22} see below {9}
{22} case 1
 
born at term (weight 2200g, length 49cm); seizures at 1y, at 12y moderate mental retardation and impaired speech. Dysmorphic face: telecanthus, hypertelorism, low-bridged nose, small mouth, micrognathia,  high-arched palate. Small hands and feet, fingers were tapering with hypoplastic nails and left clinodactyly. Obese with weight>97th centile.
  0X-W-
p11.21/
4-1
male/
2.5y
PBL de novo 47,XY,+mar[50] r(X)(::p11.21q12::)*
(XIST not present on sSMC)
FISH with different YAC probes as specified in {14} see below {14} case 1  
Patient born after uneventful pregnancy without complications; at 2.5y global developmental delay, HC at 2.5y on 10. centile; dysmorphic with moderate scaphocephaly, long philtrum, flattened nose, high arched palate, crowded dentations
  0X-W-
p11.21/
4-2
female/
9y
PBL n.a. 47,XX,+mar[10]/
46,XX[20]
r(X)(::p11.21q12::) midi; subcenM dwarphism, minor facial dysmorphism {0} provided by Dr. Albrecht, Essen, Germany  
  0X-W-
p11.21/
5-1
male/
newborn
PBL ?de novo 47,XY,+r[7]/
46,XY[23]
r(X)(::p11.21q13.1::)
aCGH: 55,260,049-68,590,017 MB
aCGH, BACs Craniofrontonasal syndrome (CFNS) caused by inactivating mutations in the gene for ephrin-B1 (EFNB1) {43}  
  0X-W-
p11.2/
1-1
male/
11y
PBL de novo?
(father n.a. for study)
47,XY,+mar[70%]/
46,XY[30%]
r(X)(::?p11.2?q12::)
(XIST not present on sSMC)
FISH showed sSMC in 251/392 metaphases)
FISH with different YAC probes as specified in {15} see below {15; 35 case 2}  
Patient with clumsiness and learning disabilities at age of 11y; mild myopia, speech normal, coordination poor; external genital immature; height between 75.-90. centile at age of 14y; father with learning disabilities, too;
  0X-W-
p11.2/
2-1
female/
13y
PBL n.a. 47,XX,+mar[4]/
46,XX[14]
min(X)(:p11.2q12:) cenM, subcenM see below {0} provided by Dr. Yurov, Moscow, Russian Federation  
developmental delay (problems with school education), hypoplasia of left kidney, hydronephrosis of right kidney, epicanthus, hypertelorism of eyes, dysplastic ear auricles, seliform nosal bridge, high-arched palate, short neck, valgus deformation of legs, hypermotility of joints, hirsutism, cyst in the left ovary, partially clinical picture of Turner syndrome (especially concerning gonads, but there is no growth retardation).
  0X-W-
p11.2/
3-1
female/
19y
PBL n.a. 47,XX,+mar[8]/
46,XX[42]
r(X)(::p11.2q13.3::)
aCGH: 63,541,782-71,253,149 
cenM subcenM, XIST; aCGH
developmental delay {0} provided by Jasen Anderson, Brisbane, Australia  
  0X-W-
p11.1/
1-1
female/
postnatal?
PBL? n.a. 47,XX,+mar[27%]/
46,XX[73%]
mar(X)(:p11.1q21.1:) array-CGH abnormal {40} case 32374  
  0X-W-
p11/
1-1
male/
prenatal
CH de novo 48,XY,+r,+r[6]/
47,XY,+r[10]/
46,XY[4]
(figures given for short term culture; in long term culture: 18/22/10)
r(X)(::p11q12~13.1::)* all available centromeric probes; wcpX; XIST-probe ; pericentric YAC probes (see {13}) see below {13}  
Chorion biopsy as fetal nuchal translucency present: thickness 4mm in week 12; in week 20 ultrasound revealed Dandy-Walker malformation with vermian agenesis, agenesis of corpus callosum and septal pellucidum, dilated ventricles; pregnancy terminated; fetopathology showed cerebral midline defects associating complete corpus callosum and septal agenesis, Dandy-Walker malformation, enlarged ventricles, dysmorphic like brachycephaly, hypertelorism, depressed nasal root, anteverted nares, cleft palate; marker presence confirmed in fetal tissue
0X-W-
p11/
2-1
female/
5y
PBL n.a. 47,XX,+mar[25%]/
46,XX[75%]
min(X)(:p11.1q11:)
possibly slightly larger - hard to determine by midi alone
midi delayed speech, hands dysmorph, double kidney left {0} provided by Dr. Weimer, Kiel, Germany
0X-W-
p11/
3-1
male/
18y
PBL n.a. 47,XY,+mar[39%]/
46,XY[61%]
min(X)(:p11.1q11:) cep XIST Klinefelter-Phenotype {0} provided by Drs. Wagner Stibbe, Hannover, Germany
                     

 

W-Cases with similar imbalances NOT caused by sSMC (W-IMB):

 

 
  case no. gender/
age at diagnosis
studied
material
de novo/
inherited
GTG-banding result and FISH result incl. grade of mosaicism test
methods
clinical symptoms reference  
  0X-W-
IMB-
q11.2/
1-1
male/
postnatal
PBL maternal (on inactivated X) 46,XY
arrayCGH: triplication in Xq11.2
62.66-63.41 MB
array-CGH see below {38}  
Patient had a condition resembling the neonatal form of spinal muscular atrophy, including extreme hypotonia, lack of reflexes, no suck or swallow, little to no movements, and congenital contractures. He died of respiratory failure at 3 weeks of age. His autopsy showed severe muscle fiber atrophy with prevalence of myofibrillar disorganization consistent with a lower motor unit disorder. The spinal cord had rare anterior horn cells with alterations suggestive of early chromatolysis.
                   


W-cases with unclear/insufficient characterization of the sSMC (CW):

 

 
  case no. gender/
age at diagnosis
studied
material
de novo/
inherited
GTG-banding result
grade of mosaicism
final result of the sSMC test
methods
clinical symptoms reference  
  0X-
CW-1
male/
2m
PBL de novo 47,XY,+mar[?%]/
46,XY[?%]
min(X) all available centromeric probes; wcpX see below {10}  
pregnancy uneventful, delivery prolonged and terminated by vacuum extraction; APGAR 8/9/10; weight: 3450g, length: 55cm, HC: 36cm; inguinal hernias and cryptorchidism; mild enlarged ventricles detected by brain ultrasound; adducted, low-set thumbs, dysplastic ears, hemangiomas of the upper eyelid, alae nasi and philtrum; severe motor and mental retardation
  0X-
CW-2
male/
prenatal
AF de novo 47,XY,+mar[50%]/
46,XY[50%]
mar present in ~80% of PBL
min(X)(:p?q13.1:)* all available centromeric probes; wcpX; XIST-probe see below {12} case 38  
birth at term, boy with deep-set ears, arachnodactyly, hyperextension of head, micropenis.
  0X-
CW-3
female/
4m
PBL de novo 47,XX,+r[23]/
46,XX[77]
r(X) cep X; XIST probe see below {21}  
pregnancy and birth normal; normal birth weight and length; later feeding problems and failure to thrive; hypotonia, developmental delay; minor anomalies, retromicrognathia, gastrointestinal reflux, mild cardiomegalie, atrial septal defect, OFC at 4.5m at 15. centile, head normocephaly, coarse hair, closed posterior fontanels, abnormal ears, clinodactyly of all four toes bilaterally
  0X-
CW-4
female/
13y
PBL n.a. 47,XX,+mar[40%]/
46,XX[60%]
r(X)
marker varied in size from cell to cell and in some cells the mass that fluoresced was several times the size of the FISH site on a normal X.
different FISH-probes:
all centromeric probes
epilepsy with developmental delay; mental retardation {7} case 5  
  0X-
CW-5
female/
12.5y
PBL n.a. 47,X,dup(X)(q?),+r[1]/
46,X,+r[7]/
46,X,dup(X)(q?)[55]
45,X[7]
r(X) wcpX Turner syndrome {16}  
  0X-
CW-6
female/
8y
PBL n.a. 47,X,der(X),+r[25%]/
46,X,der(X)[75%]
r(X) cepX Turner syndrome {17}  
  0X-
CW-7
female/
n.a.
PBL n.a. 47,XX,+mar[100%] r(X). wcpX+ wcpX, cepX see below {25}  
hypomelanosis of Ito having mental, psychomotor and speech retardation, hypotonia and behavioral problems; dysmorphism, short stature, dysgenesis corpus callosum
  0X-
CW-8
female/
1y
PBL/
buccal mucosa
n.a. 47,XX,+r[100%]
BM: mar in 40%
r(X). wcp+, cep+, XIST- wcpX, cepX, XIST see below {26}  
hypotonia, developmental delay, brachycephaly, asymmetric white matter volume loss on brain MRI;
  0X-
CW-9
n.a./
postnatal
PBL maternal 47,+r[?%]/
46[?%]
r(X). wcp+, cep+,XIST- wcpX, cepX, XIST see below {32} case 6  
developmental delay, psychomotor retardation, speech delay
  0X-
CW-10
male/
prenatal
AF and PBL de novo 47,XXY[?%]/
47,XY,+mar[?%]/
46,XY[?%]
mar(X). wcp+, cep+,XIST- wcpX, cepX, XIST see below {34}  
IUGR; postnatal growth retardation as well - but no mental problem after 36 months
  0X-
CW-11
male/
5y
PBL de novo 47,XY,+mar[17/
46,XY[83]
r(X).cep+,XIST- cepX, XIST see below {37}  
born with normal weight and bilateral cryptorchidism; at 5 y suspicion of fragile X-syndrome due to mental retardation, speech disorder, delayed development; weight and height 50-75 percentile, OFC normal;
                     

 


References

Cases with unclear clinical correlation (U)

 

 
  case no. gender/
age at diagnosis
studied
material
de novo/
inherited
GTG-banding result
grade of mosaicism
final result of the sSMC test
methods
clinical symptoms reference  
  0X-
U-1
see 15-P-2
{5} case 2  
  0X-
U-2
see mult 2-4
{6} case 3  
  0X-
U-3
male/
13m
PBL
fibroblasts
de novo 48,XXY,+r[20]/
47,XXY[30]
in fibroblasts. 40/10
r(X)(::p21q12::) cep X; wcp X; XIST specific probe see below {18}  
pregnancy and birth normal; birth weight and length <5. centile;  at 13m growth retardation; dysmorphic facial features, symmetrically microcephalic, wide spaced eyes, small palpebral fissures, epicanthal folds, short nose, flat nasal bridge; at 2.5y developmental delay
  0X-
U-4
see mult 2-8
{8}  
  0X-
U-5
see mult 2-1
{0} provided by Dr. A Dufke, Tübingen, Germany  
  0X-
U-6
female/
1y
PBL de novo 47,X,r(X),+mar[11]/
46,X,r(X)[16]/
46,X,mar[5]/
45,X[3]
r(X) with XIST
mar(X) without XIST
centromeric probe for X ; XIST probe see below {33}  
Turner syndrome phenotype; 3d after birth by caesarian section -→ hypoglycemia; birth weight 3.5 kg; at 4 months staring episodes - clonic seizures; microcephaly noticed; mild global developmental delay, normal EEG; at 11m persistent hypoglycemia, growth parameters below 3rd centile; hypertelorism, upslanting palpebral fissures, low set ears, pelvis ultrasound showed small infantile uterus but no ovaries.
  0X-
U-7
to U-8
n.a./
prenatal
AF n.a. 47,+mar[?%] mar(X) SKY no info available {36} 2 new cases  
  0X-
U-9
male/
15y
PBL n.a. 47,XYqh-,+mar[8]/
46,XYqh-[12]
min(X)(:p11.2q11:) subcenM no info available {0} provided by Dr. Iourov, Moscow, Russia
 
  0X-
U-10
female/
prenatal
PBL n.a. 47,XX,+mar[100%] min(X)(:p11.21q11.2:)[3]/
r(X)(::p11.21
q11.2::)[3]
cenM
subcenM
n.a. {0} provided from Serbia  
                     

 


References

Cases with neocentromeres (N)

 

 
  case no. gender/
age at diagnosis
studied 
material
de novo/
inherited
GTG-banding result
grade of mosaicism
final result of the sSMC test
methods
clinical symptoms reference  
  X-N-
pt22.31/
1-1
female/
newborn
PBL de novo 47,XX,+mar[100%] inv dup(X)(pterp22.31:
:p22.31
pter)
midi; telomeric probe see below {30; 36}  
born after spontaneous vaginal delivery at 40 weeks gestation. No history of miscarriages, mental retardation, or congenital defects in family; pregnancy normal. birth weight 2.84 kg. Dysmorphic features: prominent forehead, hypertelorism, down-slanting palpebral fissures, low-set/large ears, flat nasal bridge with anteverted nares and macroglossia. also umbilical hernia, hypotonia, hypermobility of joints, and congenital heart defect including ventricular septal defects, patent foramen ovale with left to right shunt, and persistent left superior vena cava draining into the coronary sinus. developed poor weight gain, gastroesophagial reflux, seizures and had severe developmental delay. At 7 m: height and weight under 5th percentile. At 4 y: only babbling and was unable to roll over.
  X-N-
qt28/
1-1
male/
13y
PBL de novo 47,XY,+mar[23]/
46,XY[27]
inv dup(X)(qterq28:
:p28
qter)
aCGH
: 152.4-154.5 MB
aCGH; FISH see below {44}  

At birth, length 52 cm (90th centile), weight 3800 g (90th centile), Apgar 8-9 (1st and 5th minutes respectively). Delayed milestones; at 3 months of age patient developed slight transitory hypertonia in lower extremities. One year later unique febrile seizure during a respiratory infection. Surgical repair of right and left inguinal hernias was carried out at the age of 4 and 6 years, respectively. At 13 years: ataxic gait; weight (70 kg), height (176 cm) head circumference (56.5 cm) >97th centile; facial dysmorphism, increased intercantal distance, large ears, bilateral single palmar crease; language delayed but he is able to make sentences.

                     

 

other neocentromere X cases (no sSMC)

Kaiser-Rogers KA, Davenport ML, Powell CM, Rao KW
A recombinant X chromosome with an atypical centromere observed in a child with Turner syndrome.
Am J Hum Genet Suppl 57:A658


 

N-Cases with similar imbalances NOT caused by sSMC (N-IMB)

 

none reported yet