Journal of Down Syndrome & Chromosome Abnormalities
Open Access

Jacobsen Syndrome its Pathophysiology, Epidemiology, Diagnosis, Management and Treatment

Sahima Jaiswal^{* *}Correspondence: Sahima Jaiswal, Department of Genetics, University of Delhi, New Delhi, India, Email:

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Introduction

Jacobsen issue (JS) is a coterminous quality condition achieved by fragmentary eradication of the long arm of chromosome 11. The condition was first depicted by Jacobsen in 1973 in a family with various people that obtained a lopsided 11;21 development got from a sensible development carrier parent. The dropping size goes from 7 to 20 Mb. The breakpoints occur inside or distal to subband 11q23.3 and the dropping ordinarily contacts the telomere. Greater terminal undoings loosening up proximal to 11q23.3 likely results in beginning phase lethality, and in some old reports of such deletions the breakpoint may have been confounded in light of specific limitations of banding objective [1]. A tremendous terminal dropping with break occurring at band 11q21 has been represented, in the mosaic construction, in a patient with a genuine complex total with holoprosencephaly and cyclopia. A partial JS total is found in three patients from an individual with a minuscule pure terminal abrogation. Fragmentary total is furthermore seen in interstitial eradications only from time to time occurring inside the JS region. Even more normally, interstitial deletions occur in 11q centromeric to the JS locale, giving a specific clinical total.

 

Epidemiology

In excess of 200 instances of JS have been so far detailed in the writing. The assessed event of JS is around 1/100,000 births. The female/male proportion is 2:1 [2].

Etiology

In JS the chromosome irregularity is for the most part an again pure terminal deletion (85% of cases). Less every so often, inconsistent developments result from disengagement of a familial changed development, as in the principal report by Jacobsen. Of course, inadequate deletion of chromosome 11q may result from lopsided developments happening once again, or from other chromosomal corrections, for instance, ring chromosomes or recombination of a parental pericentric inversion [3]. In these cases, 11q deletion is bewildered by extra lopsided characters. Chromosome 11q eradication has furthermore been represented in the mosaic design. In JS patients the beginning of the erased chromosome is bound to be maternal for breakpoints happening proximally to D11S924 (band 11q23.3), while there is a fatherly predisposition when the breakpoint is more distal. Almost certainly, engraving is engaged with the components of (CCG)n development and methylation.

Diagnosis

In patients with the conventional total the end is related on the reason with clinical revelations: mental block, facial dysmorphic components and thrombocytopenia. The finding ought to be certified by cytogenetic assessment. The clinical finding may be irksome in patients with less brand name clinical viewpoints and periphery mental development; in these cases, the impression of thrombocytopenia or pancytopenia may propose the assurance [4]. Adolescents with less signs of JS may be less disposed to be investigated ahead of schedule, considering clinical total.

Management and Treatment

After the finding of JS a total assessment ought to be performed including:

• Clinical appraisal by an overall pediatrician.

• Benchmark assessment by a pediatric cardiologist, including EKG and echocardiogram.

• Benchmark assessment by a nervous system specialist, including gauge, and conceivably sequential cerebrum imaging considers.

• Stomach ultrasound output to bar pyloric stenosis, and kidney and urinary parcel deformities.

• Ophthalmologic assessment, including widening of the students.

• Hear-able tests

• Blood tests: platelets count, platelets work considers, draining time.

• Endocrine: IGF1 and TSH

• Immunological appraisal: IgM, IgA, IgG.

As portrayed above, youngsters with JS every now and again require careful treatment intercessions [5]. Thrombocytopenia and other hematological issues should be considered preoperatively. Prophylactic bonding with platelets can be lifesaving. Because of anomalies of the pharynx keeping up with the aviation route and intubation may be troublesome.

References

1. Jacobsen P, Hauge M, Henningsen K, Hobolth N, Mikkelsen M, Philip J. An (11;21) translocation in four generations with chromosome 11 abnormalities in the offspring. A clinical, cytogenetical, and gene marker study. Hum Hered. 1973;23(6):568-585.
2. Penny LA, Dell'Aquila M, Jones MC, Bergoffen J, Cunnif C, Fryns JP, et al. Clinical and molecular characterization of patients with distal 11q deletion. Am J Hum Genet. 1995;56(3):676-683.
3. Pivnick EK, Velagaleti GV, Wilroy RS, Smith ME, Rose ME, Tipton RE, et al. Jacobsen Syndrome: Report of a patient with severe eye anomalies, growth hormone seficiency, and hypotiroidism associated with deletion 11 (q23q25) and review of 52 cases. J Med Genet. 1996;33(9):772-778.
4. Schinzel A, Der Maur PA, Moser H. Partial deletion of long arm of chromosome 11 (del (11) (q23)): Jacobsen syndrome. Two new cases and review of the clinical findings. J Med Genet. 1977;14(6):438-444.
5. Helmuth RA, Weaver DD, Wills ER, Opitz JM, Reynolds JF. Holoprosencephaly, ear abnormalities, congenital heart defect, and microphallus in a patient with 11q–mosaicism. Am J Medical Genet. 1989;32(2):178-181.