The single case report of a child with features of VATER association
and a PTEN mutation by Reardon et al., (2001) is certainly a significant
contribution to the literature. I am going to highlight it prominently in
the London Dysmorphology Database (Winter and Baraitser, 2001) (ver. 3
with significant enhancements now available from Oxford University Press).
However the case report is somewhat puz...
The single case report of a child with features of VATER association
and a PTEN mutation by Reardon et al., (2001) is certainly a significant
contribution to the literature. I am going to highlight it prominently in
the London Dysmorphology Database (Winter and Baraitser, 2001) (ver. 3
with significant enhancements now available from Oxford University Press).
However the case report is somewhat puzzling. The infant was found to have
an absent stomach bubble and polyhydramnios on ultrasonography. This was
interpreted as indicating a probable tracheo-oesophageal fistula. As far
as I am aware, an isolated tracheo-oesophageal fistula would not cause an
absent stomach bubble, unless associated with oesophageal atresia. Even
more surprising, postnatally this abnormality appears to have disappeared,
as there is no mention of investigation or treatment. I realise the
patient is probably from Ireland, where such miracles are relatively
frequent, but it would be useful to know if this malformation was
confirmed, as obviously the presence of an oesophageal abnormality
increases the overlap with VATER association. Could the authors clarify
this point?
Professor Robin M Winter
Department of Clinical Genetics
Institute of Child Health
London
Reference
Reardon W, Zhou X-P, Eng C (2001). A novel germline mutation of the PTEN
gene in a patient with macrocephaly, ventricular dilatation, and features
of VATER association. J Med Genet 2001;38:820-823.
I read with great interest this article on the mapping of an isolated
form of X-linked cataract on Xp22. As the authors state it is highly
probable that the condition in this family is an allelic form of Nance-
Horan syndrome (NHS) or cataract-dental syndrome. Although OMIM database
distinguishes NHS (MIM 302350) from two forms of isolated X-linked
congenital cataract - X-linked congenital cataract with po...
I read with great interest this article on the mapping of an isolated
form of X-linked cataract on Xp22. As the authors state it is highly
probable that the condition in this family is an allelic form of Nance-
Horan syndrome (NHS) or cataract-dental syndrome. Although OMIM database
distinguishes NHS (MIM 302350) from two forms of isolated X-linked
congenital cataract - X-linked congenital cataract with posterior sutural
opacities in heterozygotes (MIM 302200) and X-linked congenital cataract
with microcornea or slight microphthalmia (MIM 302300) - there are some
arguments suggesting that this distinction may not be justified. This
classification was based on old publications, and these two forms of X-
linked cataract without dental anomalies were described before NHS was
recognized as a distinct entity. Microcornea is part of NHS and has also
been reported in some patients within families affected with cataract from
the first group (MIM 302200) and posterior lens opacities are usually
present in NHS heterozygotes. It is highly probable that NHS was not
recognized in some families as the dental anomalies may be easily missed.
One of the NHS families included in our linkage analysis (family 2) [1]
was initially thought to be affected with an isolated X-linked cataract as
the affected males were not markedly dysmorphic and their teeth anomalies
were mild. Moreover the family reported by Krill et al. in 1969 [2], and
considered as the most convincing example of isolated X-linked congenital
cataract, was later recognized as a NHS family [3] and was included in a
linkage analysis [4]. Finally, it appears that the family described by
Waardenburg et al. in 1961 [5] and registered in OMIM database as an
isolated cataract belonging to the second group (MIM 302300), was the same
as that reported eighteen years later by van Dorp and Delleman [6] and was
ultimately recognized as a NHS family [7]. Considering this marked
phenotypic overlap, it is tempting to say that these three groups of X-
linked cataracts probably correspond to a single condition with variable
expression. The report of a first locus for isolated X-linked cataract on
Xp22 in a region overlapped by the NHS genetic interval strongly supports
this hypothesis.
References
(1) Toutain A, Ronce N, Dessay B, Robb L, Francannet C, Le Merrer M, Briard
ML, Kaplan J, Moraine C. Nance-Horan syndrome: linkage analysis in 4
families refines localisation to Xp22.31-p22.13. Hum Genet 1997;99:256-61.
(2) Krill AE, Woodbury G, Bowman JE. X-chromosomal-linked sutural
cataracts. Am J Ophthal 1969;68:867-872.
(3) Lewis RA, Nussbaum RL, Stambolian D. Mapping X-linked ophthalmic
diseases. IV. Provisional assignment of the locus for X-linked congenital
cataracts and microcornea (the Nance-Horan syndrome) to Xp22.2-Xp22.3.
Ophthalmology 1990;97:110-121.
(4) Stambolian D, Lewis RA, Buetow K, Bond A, Nussbaum R. Nance-Horan
syndrome: localization within the region Xp21.1-Xp22.3 by linkage
analysis. Am J Hum Genet 1990;47:13-19.
(5) Waardenburg PJ, Franceschetti A, Klein D. Genetics and Ophthalmology.
Vol. 1. Springfield, III.: Charles C Thomas (pub.) 1961. Pp. 880.
(6) van Dorp DB, Delleman JW. A family with X-chromosomal recessive
congenital cataract, microphthalmia, a peculiar form of the ear and dental
anomalies. J Pediat Ophthal Strabismus 1979;16:166-171.
(7) Bergen AAB, ten Brink J, Schuurman EJM, Bleeker-Wagemakers EM. Nance-
Horan syndrome: linkage analysis in a family from the Netherlands.
Genomics 1994;21:238-240.
Although I lack expertise in screening methods designed to detect the
presence of mutations that predispose to disease, the findings reported on
BRCA1 by Eng et al. are clearly important. It is essential that a
systematic blinded comparison of methods should be carried out to
establish or confirm the validity of genetic screening tests. This is of
particular importance in cases where the predisposing ris...
Although I lack expertise in screening methods designed to detect the
presence of mutations that predispose to disease, the findings reported on
BRCA1 by Eng et al. are clearly important. It is essential that a
systematic blinded comparison of methods should be carried out to
establish or confirm the validity of genetic screening tests. This is of
particular importance in cases where the predisposing risk of cancer
associated with the mutations is high and the individuals tested must make
important decisions based on the outcome of such tests. Hence, the
scientific and medical communities are obliged to assure the accuracy and
reliablity of tests offered to identify mutations that carry profound
consequences for the individual patient.
Dear Editor,
The single case report of a child with features of VATER association and a PTEN mutation by Reardon et al., (2001) is certainly a significant contribution to the literature. I am going to highlight it prominently in the London Dysmorphology Database (Winter and Baraitser, 2001) (ver. 3 with significant enhancements now available from Oxford University Press). However the case report is somewhat puz...
Dear Editr
I read with great interest this article on the mapping of an isolated form of X-linked cataract on Xp22. As the authors state it is highly probable that the condition in this family is an allelic form of Nance- Horan syndrome (NHS) or cataract-dental syndrome. Although OMIM database distinguishes NHS (MIM 302350) from two forms of isolated X-linked congenital cataract - X-linked congenital cataract with po...
Dear Editor
Although I lack expertise in screening methods designed to detect the presence of mutations that predispose to disease, the findings reported on BRCA1 by Eng et al. are clearly important. It is essential that a systematic blinded comparison of methods should be carried out to establish or confirm the validity of genetic screening tests. This is of particular importance in cases where the predisposing ris...
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