Related Experiment Videos
Partial trisomy 1q with growth hormone deficiency and normal intelligence
E K Schorry1, K N Dietrich, H M Saal
1Division of Human Genetics, Children's Hospital Medical Center, Cincinnati, Ohio 45229, USA.
Insights
This study identifies a specific genetic condition, partial trisomy 1q, linked to a familial insertion. Affected individuals may exhibit growth issues and pituitary abnormalities but can have normal intelligence.
Area of Science:
- Genetics
- Human Genetics
- Chromosomal Abnormalities
Background:
- Familial chromosomal insertions can lead to unbalanced rearrangements in offspring.
- Understanding the phenotypic consequences of specific chromosomal imbalances is crucial for genetic counseling.
Observation:
- Two siblings presented with partial trisomy 1 (q31.1-q32.1) resulting from a familial insertion of chromosome 1q into 4p.
- Patient 1 exhibited minor anomalies, short stature, growth hormone deficiency, and ectopic pituitary, but normal psychomotor development and intelligence.
- Patient 2 presented with intrauterine growth retardation, sharing the same partial trisomy 1q.
Findings:
- Partial trisomy 1(q31.1-q32.1) is associated with prenatal and postnatal growth retardation.
- Observed features include narrow palpebral fissures, microphthalmia, and microstomia.
- Pituitary abnormalities and normal intelligence were noted in affected individuals.
Implications:
- Recognition of a distinct phenotype for trisomy 1(q31.1-q32.1) aids in diagnosis and management.
- This finding highlights the importance of detailed cytogenetic analysis in cases of developmental delay and growth abnormalities.
- Further research can elucidate the specific genes within the trisomic region responsible for the observed phenotype.
Abstract:
We present two sibs with partial trisomy 1 (q31.1-q32.1) due to a familial insertion. Patient 1 is a girl who presented at age 9 months with minor anomalies, short stature, and normal psychomotor development. Karyotype was 46,XX,der(4)ins(4;1) (p14;q31.1q32.1)pat. The father had a balanced inverted insertion of 1q into 4p, with karyotype 46,XY,ins(4;1)(p14;q31.1q32.1). At age 5 years, patient 1 was found to have short stature with documented growth hormone deficiency and ectopic pituitary. Her growth velocity responded well to treatment with growth hormone. Cognitive testing at 5 9/12 years showed normal intelligence with an IQ of 90. Patient 2, the brother of patient 1, presented with intrauterine growth retardation. He has the same chromosomal insertion as his sister, with partial trisomy 1q. We suggest that there is a recognizable phenotype of trisomy 1(q31.1-q32.1) which includes prenatal and postnatal growth retardation, narrow palpebral fissures, microphthalmia, microstomia, pituitary abnormalities, and normal intelligence in some individuals.