Discussion
In 1987, Morse et al. (1987) described two consecutive male fetuses that presented decreased fetal activity, multiple congenital contractures, microcephaly and holoprosencephaly (Table 1). These abnormalities were detected by ultrasound during the second trimester of gestation. The parents were young and non-consanguineous and had a normal daughter. The likely inheritance in these cases was considered to be autosomal recessive or X-linked1. Shortly after, in 1988, Hockey et al, described two stillborn males whose mothers were sisters, presenting holoprosencephaly, hypokinesia, microcephaly and multiple contractures (Table 1). The diagnosis of Morse syndrome was established, and the authors suggested that this is an entity with X-linked inheritance rather than autosomal recessive2. Morse et al (1987) reviewed the reported central nervous system abnormalities associated with the Pena-Shokeir syndrome (intrauterine growth retardation, facial anomalies, contractures, and pulmonary hypoplasia with normal chromosomes). None of the findings of Morse syndrome is consistently associated with Pena-Shokeir syndrome; also, holoprosencephaly usually occurs without the stigmata of Pena-Shokeir syndrome1. Our patient was a male child who presented all the abnormalities reported by Morse et al and Hockey: decreased fetal activity, multiple congenital contractures, microcephaly and holoprosencephaly. Although autosomal recessive inheritance can not be ruled out, we believe that the following evidence support the hypothesis of X-linked inheritance: no consanguinity in any of the reported cases; recurrence in all families previously described; all the reported cases, including the present one, were male.
Table 1: Clinical and ultrasound findings in reported cases with holoprosencephaly-hypokinesia syndrome (Morse syndrome).
Finding
|
Morse et al (1987)
|
Hockey et al. (1988)
|
Case 1
|
Case 2
|
Case 1
|
Case 2
|
Present case
|
Diminished fetal activity
|
+
|
+
|
+
|
+
|
+
|
Multiple contractures
|
+
|
+
|
+
|
+
|
+
|
Microcephaly
|
+
|
+
|
+
|
+
|
+
|
Holoprosencephaly
|
+
|
+
|
+
|
+
|
+
|
IUGR
|
+
|
+
|
+
|
+
|
+
|
Micrognathia
|
+
|
NR
|
NR
|
NR
|
+
|
Prominent lateral gengival ridges
|
+
|
NR
|
NR
|
NR
|
+
|
Muscular atrophy of lower limbs
|
+
|
+
|
NR
|
NR
|
+
|
Male gender
|
+
|
+
|
+
|
+
|
+
|
Karyotype 46,XY
|
+
|
+
|
+
|
NR
|
+
|
Skin abnormalities
|
-
|
-
|
-
|
-
|
Jaundice, petechias
|
NR = not reported.
References
1.      Morse RP, Rawnsley E, Sargent S, Graham JM. 1987. Prenatal diagnosis of a new syndrome: holoprosencephaly with hypokinesia. Prenat Diagn 7, 631-638.
2.      Hockey A, Crowhurst J, Cullity G. 1988. Microcephaly, holoprosencephaly, hypokinesia – second report of a new syndrome. Prenat Diagn 8,683-686.